SEMI-ANNUAL PERFORMANCE REPORT Mote Marine Laboratory Technical Report No: 1082

Award Number: NA16FL2813

Amount of Award: Federal Share $ 1,825,929

Project Title: Highly Migratory Shark Fisheries Research by the National Shark Research Consortium (NSRC), 2005-2006

Recipient: Mote Marine Laboratory, Sarasota, Florida

Award Period: July 1, 2005 to June 30, 2006

Period Covered by this Report: July 1, 2005 to December 31 , 2005

Primary Project Tasks:

The following primary tasks were scheduled for this six-month period:

Mote Marine Laboratory Component

la. Shark life history, migration and stock structure

1 b. Satellite tag testing and development

lc. Navigation and orientation

I d. Relative abundance

Ie. Population and ecosystem

I f. Freshwater habitat use

19. EFH environmental studies

lh. Nurse shark reproduction

I i. Whale shark research in the Gulf of Mexico and Caribbean Sea

Ij . Publications and scientific conferences

Moss Landing Marine Laboratories Component

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2a. Eastern North Pacific chondrichthyan life history data matrix

2b. Age, growth, and demographic studies

2c. Age validation studies

2d. Reproductive biology

2e. Feeding ecology

2f. Stable isotope analysis

2g. Habitat associations and nursery grounds

2h. Population genetic studies

2i. Shelf, slope and pelagic surveys

2j . Eastern Pacific shark fisheries analysis

2k. Taxonomic studies

21. Publications/conferences Virginia Institute of Marine Science

Component

3a. Relative abundance and distribution studies

3b. Age, growth, and demographic studies

3c. Habitat utilization and migration studies

3d. Shark energetic and osmoregulatory studies

3e. Shark genetics

3f. Publications and conferences

University of Florida Component

4a. Fishery independent sampling

4b. Age, growth, and reproduction

4c. Skate life history

4d. Tagging/tracking

4e. Age-structured model

4f. International Shark Attack File

4g. Web/media education

4h. Classroom education

4i. Requests for information

4j . Publications and conferences

Summary of Results:

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General Project Overview

Significant progress was made during this six-month period ofthe project. Important advances by the NSRC were made in both field and laboratory approaches to understanding the life history, abundance and environmental biology of shark species important in commercial and recreational fisheries. NSRC researchers and students continued to make significant scientific contributions through publications and conference presentations during the six-month period. There were no major problems experienced with the overall project during the period.

Mote Marine Laboratory Report (R. Hueter, P/I)

Mote's Center for Shark Research (CSR) served as project coordinator. No problems were encountered in the administration of the project. The following technical accomplishments were achieved during the reporting period:

la. Shark life history, migration and stock structure. From July through December 2005, the Mote CSR captured a total of 175 sharks of 8 species. Of these sharks, 95 were tagged and released. During this same period, 22 recaptured sharks were reported and logged in the CSR <Jatabase. Of these, the longest at large was a bull shark (Carcharhinus leucas) tagged in October of2002 during CSR quarterly surveys off Longboat Key. It was recaptured in September of2005 after 1,083 days (2.97 yrs) at liberty, off Apalachicola, Florida, about 136 nm (252 km) from its original tagging site. The longest minimum at-sea distance traveled in these recaptures was reported from a juvenile blacktip shark tagged off Yankeetown, Florida in August of2004. This shark was recaptured in July of2005 off Broken Islands in Charlotte Harbor, Florida, about 149 nm (276 km) from its tagging site.

Two surveys for large coastal sharks were undertaken during the period, one in fall (Sept 2005) and one in winter (Dec 2005) in the waters off Sarasota. The fall survey was conducted aboard the RIV Eugenie Clark and consisted of only 2 days of fishing due to a severe red tide outbreak (from the dinotlegellate Karenia brevis) in the area. This type of harmful algal bloom is known to have a significant impact on shark movement patterns. Consequently, no sharks were captured during the two days of fishing on this trip. The winter trip, which utilized the Florida Institute of Oceanography vessel RlV Suncoaster, also consisted of2 days oflongline and drumline sampling. This survey captured 19 sharks, comprising C. brevi pinna (13), C. aero notus (4) and C. plumbeus (2). Several mechanical problems with the vessel shortened this trip's duration from 5 to 2 days.

To further development a biomarker for bonnethead sharks (Sphyrna tiburo) exposed to estrogen-like pollutants, a total of 1 0 gill net sets were conducted to collect specimens of this species in the areas of Tampa Bay, Charlotte Harbor, Biscayne Bay, and the Florida Keys. · A total of92 sharks were captured comprising S. tiburo (78) and C. limbatus (14) with nearly half of these sharks being tagged and released.

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lb. Satellite tag testing and development Tank-testing of satellite tags was not conducted during this period as the research tanks of Mote CSR's MERF (Marine Experimental Research Facility) were in use for other projects. However, field studies using PAT satellite tags continued. Wildlife Computers P AT tags were deployed on three species of shark during the study period - two whale sharks (Rhincodon typus) , one sawfish (Pristis clavata) and two blacktip sharks (Carcharhinus limbatus). All five tags released reported data to MML researchers. Results ofthe whale shark tags are described in a section below. The sawfish tagged demonstrated a high level of site fidelity, but depth data returned provided information on excursions from its regular home range. The tag from one of the two blacktip sharks was returned after washing up on a beach. This tag had detached from the shark after less than seven days. The other blacktip tag remained on the shark as programmed. The tag surfaced near Cuba and downloaded valuable data on movements of this species. The success of these tag deployments in light of previous difficulties indicates that the testing and development being undertaken with this project is providing increased effectiveness ofthis useful tagging methodology. Planned tank testing of satellite tag attachment and design should commence shortly as other experiments in the holding tanks have now been completed.

lc. Navigation and orientation. Translocation studies to examine site and nursery area fidelity of juvenile blacktip sharks were successfully initiated in 2005. Six native sharks within Terra Ceia Bay were collected, held under transport conditions for 3 hours, fitted with acoustic transmitters and released in good condition. After the successful release of these individuals sharks were collected within Pine Island Sound and transported (3 hours) to Terra Ceia Bay. Eleven individuals were transported and nine were considered in good enough condition to fit with acoustic transmitters and release. All sharks were monitored via the acoustic monitoring network and none suffered mortality immediately post-release. Individual sharks showed varying movement patterns with translocated sharks tending to use more of the study site than native sharks. However, only two weeks of data were collected with all sharks present within the study site. At that point an extensive, intense red tide algal bloom moved into the study site causing large-scale morality of sharks, rays and teleosts. All individuals fitted with transmitters suffered mortality during this event and no further data were collected. Although data concerning residence and movement patterns were not useful, the initial results of this study suggest that this type ofproject can be successfully carried out and useful results obtained.

ld. Relative abundance. During the period of this report, no blacktip relative abundance sets in primary nurseries were conducted as these field activties were suspended in 2005 due to concerns over high mortality of pups in the nursery as a result of red tide, as well as the direct effects of our own gillnet fishing. In lieu continued field work, a large-scale analysis of this project's 10-year dataset of three Florida Gulf coast nurseries (Yankeetown, lower Tampa Bay and Pine Island Sound) was conducted and its results presented at the annual American Elasmobranch Society Meeting, July 2005, in Tampa. Overall, 970 quantitative gill nets sets were made between 1995 and 2004 resulting in the capture of 8,257 sharks of thirteen species, of which 3,842 were juvenile blacktips. Recaptures have been reported from 151 of the tagged sharks comprising 5 species. First-year blacktips have demonstrated movements of more than 280 nautical miles after leaving their summer nursery grounds. Recapture data further indicates a pattern of sharks returning to their natal nursery areas the following season and in subsequent years. A general linear model was used to standardize the CPUE data. Significant differences in the juvenile blacktip catch were found between years, nursery areas, and between grids within a nursery area. When looking at the blacktip catch rates over the entire 1 O-year period, there were no apparent trends that would be indicative of population

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level changes despite stock assessments indicating an increasing abundance ofblacktip sharks in the U.S. Atlantic and Gulf of Mexico since the mid 1990s. The ability these surveys to detect changes in recruitment in the nursery areas may have been influenced by environmental perturbations such as red tide blooms and localized salinity drops from severe storm events.

Ie. Population modeling and ecosystem studies. Studies of shark populations and how they respond to localized fishing were initiated in December 2004 and continued through this reporting period. Dr. Sheldon Dudley of the Natal Sharks Board and Dr. Simpfendorfer ofMML analyzed data from 14 species of sharks that have been fished since the 1950s in the waters off South Africa. Analysis of data from this project has demonstrated that even in situations where regular fishing occurs on shark populations, they are able to reach equilibrium yield levels. This result demonstrates that all shark species, even those with K-selected life histories (e.g. dusky sharks), have density­dependent population processes and so can sustain some level of fishing. Analysis of beach-by­beach catch rates of commonly captured sharks also indicated that localized depletion oflarge shark species occurs at scales less than 50km, indicating that even these larger sharks may have relatively high site fidelity. Analysis of historic catches ofbatoids on the west coast of Florida began to be examined during the study period. Data from 1950's and 1960's catches made by Dr. Eugenie Clark and collaborators were extracted from original logbooks and entered into a spreadsheet for analysis.

If. Freshwater habitat use. In 2005 studies of freshwater habitat use by bull sharks continued in cooperation with the South Florida Water Management District and the Florida Wildlife Research Institute. Both of these agencies are very interested in the results of this research and in continued collaboration to expand and utilize the data collected in this study. A total of 24 bull sharks were fitted with acoustic transmitters in 2005 and by the end of the year 11 of those individuals still remained within the river and six individuals from 2004 studies were still present. In addition, seven endangered smalltooth sawfish were fitted with transmitters within this system in 2005 and data concerning their residence and movement patterns were collected. Individual bull sharks monitored from both years are displaying patterns of habitat use consistent with direct responses to changes in salinity level (data from sawfish have not been analyzed in enough detail to draw any conclusions regarding their movements in relation to salinity). The data from this study are currently being processed and analyzed with at least one scientific publication expected from this work in 2006.

Although current data suggest that individuals within the river system more information is needed to better understand the underlying mechanisms of freshwater habitat use to be able to predict use of other river systems by bull sharks. In an effort to collect and incorporate the required data Dr. Heupel has formed a collaboration with scientists at UC Davis to examine physiological condition and responses of bull sharks to salinity change. In addition funds have been requested from the Florida Non-Game Wildlife Program to establish a complementary acoustic array in a nearby river that is less affected by freshwater change due to its more natural state. Finally, Ms. Lori Ortega, a Masters student at the University of Florida will become involved in this project in 2006 to examine shark movement patterns based on depth preference and position in the water column in relation to the picnocline.

19. Essential Fish Habitat environmental studies. Previous CSR studies have demonstrated that shark populations residing in some nursery areas on the U.S. east coast are exposed to and accumulate potentially hazardous levels of certain endocrine-disrupting pollutants, such as organochlorine pesticides and polychlorinated biphenyls. Because of this, the goal of our

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environmental research is to detennine ifthese and other aquatic contaminants reduce the quality of EFH and, in tum, the health and sustainability of coastal shark populations. Our research objectives for 2005-2006 were to:

1. Use a newly developed assay for gene expression of the pollutant biomarker, vitellogenin, to detect exposure and effects of estrogen-mimicking compounds in sharks and rays residing in federally managed shark EFH.

2. Continue to develop more sensitive genetic techniques for detecting pollutant exposure and effects in sharks and rays.

3. Examine concentrations of other environmentally relevant pollutants in Atlantic and Gulf coast sharks, such as compounds used in human phannaceuticals and breakdown products of detergents and other household items.

We focused largely on objective 1 during the first half of the granting period. Between late summer and fall 2006, we collected liver samples from >40 male and immature female bonnethead sharks from important shark nurseries in Georgia, South Carolina, and Florida. Combined with our previous samples, this brings us to a total of> 100 liver samples obtained from bonnethead sharks from 6 distinct nursery habitats on the U.S. east coast. Total RNA was extracted from liver of these animals and tested for the expression ofvitellogenin, a bioindicator of estrogenic pollutant exposure and effects in non-mammalian vertebrates. This was accomplished using a newly developed RT­PCR assay for vitellogenin mRNA, which is more sensitive and requires less tissue to perfonn than our previously constructed Northern Blot assay. Our preliminary results indicate that sharks residing in these locations do not exhibit physiological responses to estrogen-mimicking pollutants. This even appears to be true for Atlantic coast sharks, which may be exposed to significantly higher levels of organochlorine pesticides than their Gulf coast counterparts based on our earlier studies. Since these previous data were obtained for blacktip sharks, we also collected liver samples for organochlorine contaminant analysis from bonnetheads in summer of2005. These studies confirmed that Atlantic coast bonnetheads also accumulate greater levels of pesticides and PCBs than Gulf coast conspecifics. However, as demonstrated by our vitellogenin studies, these levels do not appear to be high enough to cause physiological effects.

In addition to our vitellogenin studies, we also continued work on developing more sensitive genetic procedures for detecting pollutant exposure and effects in sharks and their relatives. Working with EcoArray Inc., a leader in the development of custom gene chips for aquatic organisms, we cloned > 140 gene sequences from the liver and testis of male bonnethead sharks that change in expression in animals exposed to estrogen-like substances. Combined with our previous data on blood cell genes, this gives us over 250 candidate gene sequences that may be useful for detecting estrogenic pollutant exposure in sharks with high resolution via microarray (gene chip) analysis. In the upcoming months, we intend to construct a "test" gene chip using ~ 200 of these sequences and evaluate its usefulness as a chemical-specific pollutant screen for sharks exposed to a number of common estrogen-mimicking pollutants. This will be accomplished using sharks experimentally treated with either the synthetic "birth control" estrogen, ethinylestradiol; the detergent surfactant, nonylphenol; or the DDT metabolite, DDE.

1 h. Nurse shark reproduction. Field research into the natural reproductive cycle of the nurse shark,

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Ginglymostoma cirratum, was conducted in the Dry Tortugas, Florida during this reporting period. We spent 21 days on site observing the mating systems and behavior of nurse sharks in collaboration with colleagues from Albion College, Michigan, Southern Illinois University, Florida International University and National Geographic's Remote imaging, Washington, D.C. We were supported on site by the vessel SN Eos, the RN Tiburon and the National Park Service at Fort Jefferson. This year a re-engineered version of the animal borne instrument package, "Crittercam" again provided unique oppertunities to view the in 'situ' activities of our mating sharks. This was the last of three years of cooperative development, engineering and observational deployment of this instrument package. We placed 16 coded transmitters on mating sharks in July of 2005. Data from these transmitters showed that shallow water shark mating was only delayed, not stopped, by a tropical storm. Hurricane Dennis (July 9th) was the first of four hurricanes to directly impact the Dry Tortugas during 2005. Eleven of our transmittered mating sharks were present before and after the hurricane. They departed our shallow study site and returned an average of 36 hours later after Dennis had passed. Our annual fall research expedition to investigate the shallow water behavior of pregnant female sharks was delayed by repeated Florida hurricanes until mid-November 2005 . We located and downloaded eight of nine of our hydrophone receivers. One was buried under two feet ofhurricane deposited rock. Changes to our study area were amazing. The ephemeral islands of the Dry Tortugas were stripped, eroded, cut and transformed by the storms of2005. Bird Key not seen since the 1930's surfaced after 75 years underwater. Unaffected by hurricanes, adult female sharks continued to use the habitat as before. Our hydrophone array recorded all nine ofthe female sharks transmittered last June and revealed that seven were using the shallow flats for reproductive habitat as late as November 16th while they await parturition. We are in the process of analyzing environmental data to try to explain and predict this occurrence of pregnant females. One male was picked up by a hydrophone array south of Miami on August 4th. It will be interesting to see if this male returns to the Dry Tortugas for the 2006 mating season.

Ongoing tag retention studies on five nurse sharks held captive at the Summerland Key Lab and at Mote's Key West facility have shown that aquarium tag retention is a high as in the field. We are now investigating different tag types for longevity.

1 i. Whale shark research in the Gulf of Mexico and Caribbean Sea. During the period of this report, Mote's CSR scientists continued theirresearch on whale sharks (Rhincodon typus) throu~ its collaboration with Mexican scientists and resource managers with the Comisi6n Nacional de Areas Naturales Protegidas (CONANP) of the federal Secretaria de Medio Ambiente y Recursos Naturales (SEMARNA T) in Cancun, Quintana Roo. This study aims to document the size and characteristics of a unique aggregation of whale sharks in the Gulf and Caribbean waters off Mexico's Yucatan Peninsula. Part of the CSR's role in this collaboration is to provide expertise that will explore the connectiveness of Gulf, Caribbean and other oceanic habitats in the life history of whale sharks as well as help develop resource management and ecotourism plans for conservation of this unique species in Mexico. In early September of 2005, Mote scientists deployed P AT tags on 2 juvenile male whale sharks in the Isla Contoy/Isla Holbox areas of the Yucatan. These two sharks were both sub-adult males of similar size (5.5-6.0 m TL). The tags reported as planned after a 30-day deployment and detailed data reports were received on both sharks. One ofthe sharks had its tag pop off some 475 nm to the WNW of its original tag site. The second shark demonstrated southerly movements into the Caribbean as its tag came off about 145 nm from its point oftagging. This is the first evidence that the whale sharks in the summer aggregation off the Yucatan may travel from different parts of the Gulf of Mexico and Caribbean to utilize this habitat. Preliminary analysis of depth data logged on these tags demonstrates regular dives to depths of at least 980 m. Mote

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scientists also participated in an integrative workshop on the conservation and preservation of whale sharks (Aug 29-31, 2005, Isla Holbox, Mx). This meeting brought local resource managers, scientists and ecotourism operators together to develop management strategies to ensure the protection of this species.

Publications and scientific conferences. During the reporting period Mote CSR scientists participated in several international conferences including the International Whale Shark Conference in Australia, a workshop of the IUCN Shark Specialist Group in the UK, and the American Society of Limnology and Oceanography annual meeting in Salt Lake City, Utah. Dr. Hueter participated in a meeting of the NOAA Highly Migratory Species Advisory Panel in Silver Spring, Maryland in March. During the reporting period CSR scientists had ten peer-reviewed publications appear or in press.

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Moss Landing Marine Laboratories Report (G. Cailliet, P/I)

2a. Life history data matrix. The life history data matrix (LHDM) is available on the PSRC web site for the general public (http://psrc.mlml.calstate.edu) and can be downloaded. The LHDM was compiled, organized, and edited, using all pertinent regional literature to determine what is known and, more importantly, what is not known about the life history, distribution, and population biology of eastern North Pacific Ocean (ENP) chondrichthyans (including the sharks, rays and chimaeras). The ENP as defined here includes the area ranging from the eastern Bering Sea to the southern tip of the Baja California peninsula. The LHM includes 105 species of chondrichthyans reported to occur in the ENP. The LHM will be updated periodically as new information becomes available.

2b. Age, growth, and demographic studies. Age determination and validation studies are continuing to fill some of the gaps in the life history of poorly studied species. Studies completed, or nearing completion, include the sandpaper (Bathyraja kincaidii), roughtail (Bathyraja trachura), California (Raja inornata), and longnose (Raja rhina) skates. Age estimates have been, or are currently being, calculated for all of the aforementioned species with ages at 50% maturity estimated for the sandpaper skate at 6.8 years for females and 7.3 years for males, roughtail skates at 9 years for females and 10 years for males, California skate at 8 years for females and 7 years for males, and longnose skates at 16 for females and 14 for males. The sandpaper skate age and growth study was completed as a Masters thesis during this report period. Additional vertebrae for the roughtail skate are still being sectioned and age estimations of California and roughtail skates are still being completed. A collaborative effort between PSRC personnel and researchers at Oregon State University has resulted in the completion of a Masters thesis during this report period on the age and growth of the longnose skate.

The growth characteristics of the California skate are being determined using three ageing structures and seven different growth models. The suitability of neural arches and caudal thorns as alternative ageing structures was examined. Neural arches appear to be poorly calcified and lack patterns that could be consistently interpreted for age estimation. Our analysis suggests that caudal thorns of this species grow at differential rates or are replaced and therefore also do not appear to be a suitable ageing structure for this species. Caudal thorns are continuing to be prepared and examined for other skates, including the sandpaper and roughtail, for potential use as a non-lethal means to age skates. Preliminary age estimates using caudal thorns for these latter two species appear to underestimate age relative to band counts taken from vertebral centra.

Demographic analyses of California, roughtail, and sandpaper skates based on vital rates will be calculated in the future by PSRC personnel. Results from this portion of the study will provide critical baseline information necessary for the effective management of these skates.

2c. Age validation studies and stable isotopes. Validation of the periodicity of growth band deposition in shark vertebrae and age estimates based on vertebral band counts using bomb radiocarbon are nearing completion for two species and continuing for two others. To date, age validation research has successfully resolved the number of bands that are formed annually within the vertebrae of short fin mako (Isurus oxyrinchus). Using bomb radiocarbon analysis we were able to validate the ageing methodology that assumed annual deposition of one pair of vertebral bands. Results of previous studies were inconclusive, leading some to base growth rates and management strategies on the assumption of one band pair formed annually and others to hypothesize that two band pairs were formed annually. This portion of the project was carried out as part of a Masters

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thesis, which has now been completed. The results are that the shortfin mako deposits two bands (one band pair) per year, based upon bomb radiocarbon age validation techniques. We have also analyzed white shark (Carcharodon carcharias) vertebrae for bomb radiocarbon and stable isotopes (C-13, N-15) composition to validate the age estimates and assess trophic level. Papers resulting from these two studies have been accepted for publication and are now in press. We are also continuing bomb radiocarbon age validation studies on northwest Atlantic species, including the sandbar ( Carcharhinus plumbeus) and tiger (Galeocerdo cuvier) sharks, using vertebrae from several institutions including the Florida Program for Shark Research at the University of Florida and the National Marine Fisheries Service Narragansett Laboratory in Rhode Island.

2d. Reproduction. Investigations of the reproductive biology based on 304 California, 1,179 longnose, 589 roughtail, and 296 sandpaper skates are continuing or nearing completion. A reproductive study of the sandpaper skate was conducted as part of a Masters thesis that was completed during this report period. Reproductive studies of the California and longnose skates are nearing completion and will result in two manuscripts to be completed by PSRC staff. Analysis and collection of roughtail skate reproductive data are complete and data are being analyzed and incorporated into a Masters thesis. A study on the reproductive biology and distribution of eastern North Pacific deepsea catsharks (Scyliorhinidae) was completed as a Masters thesis and results from that study are being prepared for publication. Information and results on the distribution and reproduction of these catsharks were generated from specimens collected by fishery independent survey cruises from June 2001 through October 2004 between northern Washington and San Diego, California. Longline catches consisted mainly of filetail catsharks (Parmaturus xaniurus), with gravid female brown catsharks (Apristurus brunneus) occasionally. Conversely, trawl catches consisted mainly of Apristurus species. Brown catsharks were typically found between 300 and 942 m, whereas longnose catsharks (A. kampae) occurred > 1,000 m depth. Filetail catshark were caught between 300 and 550 m depth. Total length at first, 50% and 100% maturity were determined for males and females of all three species. At higher latitudes, brown and filetail catsharks reached sexual maturity at larger sizes. Brown and filetail catsharks reproduce year-round, based on the temporal occurrence of gravid females and the lack of seasonal variation in gonadosomatic (GSI) and hepatosomatic indices (HSI) for both males and females. Gravid longnose catshark females were found from July through December. The egg case of the longnose catshark has been described and its morphology compared to the egg cases of the brown, filetail and other Apristurus species. Additional studies on the reproductive biology of other eastern North Pacific chondrichthyans, including the big (Raja binoculata) and starry (Raja stellulata) skates and white-spot chimaera (Hydrolagus colliei), are continuing.

2e. Feeding ecology. Dietary analyses of sandpaper, big, California, and longnose skate feeding ecology is continuing or nearing completion. Approximately 493 sandpaper skates have been examined to date with shrimps, euphausids, and mysids being the primary prey items, followed by polychaetes, teleosts (Sebastes spp.), and cephalopods. Prey items from approximately 618 longnose skate stomachs have been examined and identified. The main prey items appear to be teleosts, crangonid shrimps, and euphausiids. Both the sandpaper and longnose skate studies are nearing completion and each will be written up as a Masters thesis. Dietary analysis of 205 big and 287 California skates has been completed. The big skate feeds primarily on demersal teleosts, crustaceans, and cephalopods, whereas the California skate feeds mainly on benthic shrimp, crabs, and demersal teleosts.

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2f. Stable isotope analysis.

2g. Habitat and nursery ground studies. Research concerning habitat associations, distribution, and abundance of eastern North Pacific chondrichthyans was continued during this report period. Study species include several deepsea catshark, skate, and chimaera species. Habitat-specific distribution and abundance of brown and filetail catshark egg cases was determined by trawl surveys and observations of archival video footage taken by remotely operated vehicle. These egg cases were located in specific sites on areas of high vertical relief at 300 to 400 m depth. Two new species of chimaeras were identified from archived video available through the Monterey Bay Aquarium Research Institute (MBARI).

The field portion of a tracking study on the movement patterns of leopard sharks (Triakis semifasciata) in Elkhorn Slough is complete and data are still being analyzed. A GIS habitat map is being constructed for Elkhorn Slough for use in analyzing the active tracking data. Once this map is complete, analyses of habitat utilization, rates of movement, tidal movements, and space activity can be initiated. Preliminary analyses indicate that the movement patterns ofleopard sharks appear to be highly influenced by the tides and suggest that they may utilize some areas more intensively than others.

A study on the occurrence of prickly sharks (Echinorhinus cookei) at the head of the Monterey Bay Submarine Canyon is continuing. This study is tracking the movements ofthis large deepsea shark to determine why this species moves into shallow water. To date 15 sharks have been tagged and tracked.

2h. Population genetic studies. Genetic research has been completed on all three thresher shark species; Alopias pelagicus, A. superci!iosus, and A. vulpinus. A total of302 samples was obtained from shark populations in the North and South Pacific, North Atlantic, and southwestern Indian Oceans. Sequence data and chromatograms were analyzed for 263 of those samples. Data analysis indicates that significant population structure exists for all three Alopias species, the scale ofwhich differs depending on the species. This project was completed and written up as a Masters thesis during this report period. The results are being prepared for publication.

2i. Shelf, slope and pelagic surveys. In cooperation with NMFS Northwest Fisheries Science Center (NWFSC) and Santa Cruz Lab, PSRC personnel are continuing to participate and assist in the annual shelf and slope groundfish surveys off Washington, Oregon, and California. We are continuing to record chondrichthyan landings from semi-monthly NMFS SCL trawl and longline surveys in Monterey Bay. Measurements, wet weights, reproductive tracts, tissue samples, parasites, vertebrae for age and growth estimation, and/or stomachs for feeding analyses have been collected from over 5,000 specimens to date. The primary elasmobranchs observed in NMFS SCL groundfish surveys are the big, California, and longnose skates, spiny dogfish (Squalus acanthias), and white­spotted chimaera. PSRC personnel participated in the NMFS Alaska Fisheries Science Center (AFSC) 2005 Gulf of Alaska survey. Reproductive data and vertebrae for age and growth, and stomachs for diet studies were collected. These data are being utilized for new life history projects on Alaskan skates.

2j. Chondrichthyan fishery database. A regional fisheries database, incorporating all chondrichthyan species landed in waters of the western continental United States is nearing completion. Focus has been directed at acquiring and entering commercial and recreational chondrichthyan fishery landings and regulations from Alaska, California, Oregon, and Washington

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from 1980 to present. Details were obtained from the Pacific States Marine Fisheries Commission via the RecFin and PacFIN databases, and through state fisheries agencies. Relevant peer-reviewed publications, technical reports, and management/regulatory plans have been acquired and incorporated into the database. State-specific information will be provided for public access through the PSRC website and available later in 2006.

2k. Taxonomic studies. A review and revision of eastern North Pacific skates genus Bathyraja (Family: Arhynchobatidae) are ongoing. Colleagues at the NWFSC, with assistance from PSRC personnel, are continuing to collect and save skates during their annual slope cruises. Supplemental material was collected during the AFSC 2005 Gulf of Alaska survey. A revised key to the skate egg cases of the eastern North Pacific is in progress. It is anticipated that this revised key will complement one recently completed for the eastern Bering Sea by PSRC staff. In addition, specimens from museum collections at the California Academy of Sciences, Los Angeles County Museum Natural History, Smithsonian Natural History Museum, Scripps Institution of Oceanography, and the University of Washington will continue to be examined. PSRC personnel are continuing to consult and collaborate on this project with leading experts at the Shark Research Center, Cape Town, South Africa, CSIRO, Hobart, Tasmania, Australia, and at Texas A & M University, Galveston, Texas. In collaboration with colleagues from Millersville State University and the California Academy of Sciences a review of eastern Pacific chimaeras has revealed several new species; two of which were prepared and submitted for publication.

2L Publications and conferences. Members of the PSRC attended and presented results of our research at the American Elasmobranch Society meetings in Tampa, Florida, the American Fisheries Society meetings in Anchorage, Alaska, and at the Western Society of Naturalists meetings in Monterey, California. In total, 13 oral and 4 poster presentations were given. The PSRC web site "Featured Elasmobranch" that highlights a different species each month continues to attract attention from the general public, especially educators, who visit the web site on a regular basis to find out more about our ongoing research efforts. PSRC staff produced a total of 11 papers during this report period that are published, in press, or in review.

Virginia Institute of Marine Science Report (1. Musick, P/I)

3a. Relative abundance and distribution studies. During the report period, 32 longline sets were made in the Chesapeake Bay and coastal waters of Virginia and New Jersey. These sets fished 1,258 standard hooks, 360 non-standard hooks (directed toward juvenile sandbar sharks), and 1,910 Japanese style tuna hooks. The catch included a total of 177 sharks: 66 sandbar sharks (Carcharhinus plumbeus), 34 smooth dogfish (Mustelus canis), three spiny dogfish (Squalus acanthias), 29 dusky sharks (Carcharhinus obscurus), 34 Atlantic sharpnose sharks (Rhizoprionodon terraenovae), six shortfin mako sharks (Jsurus oxyrhinchus), one spinner shark (Carcharhinus brevi pinna), and one scalloped hammerhead shark (Sphyrna lewini), one tiger shark (Galeocerdo cuvier) , one common thresher shark (Alopias vulpinus), and one sandtiger shark (Carcharias taurus). The sharks captured were either sampled for age and growth, tagged with VIMS juvenile dart tags, or tagged with NMFS M-type dart tags. During the time period 115 sharks were tagged. All sharks were sampled for DNA analysis. In addition skates and rays of three

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different species were captured: 12 cleamose skates (Raja eglanteria), two roughtail rays (Dasyatis centroura), and one cownose ray (Rhinoptera bonasus).

VIMS scientists continue to collaborate with scientists from Alaska Department ofFish and Game to develop techniques using side-scan sonar to assess salmon shark stocks in the fjords adjacent to Prince William Sound. Preliminary studies in summer 2000 using sonically tagged sharks (known targets) suggested that an exploratory side scan sonar survey using a line transect design would be possible in selected fjords in summer 2002. This exploratory research was successful and a second acoustic survey during August 2004 was conducted to monitor salmon shark abundance and the presence of prey species (schools of herring or salmon). To further monitor abundance, longline sets were made in these areas to capture and tag salmon sharks. During this cruise three salmon sharks were outfitted with thermister tags to monitor the thermal inertia exhibited by salmon sharks, more specifically to monitor temperature changes in the inter-muscular rete. A third acoustic and sampling survey trip was conducted in August 2005. During this cruise two thermister tags were deployed in the same fashion as in the previous cruise. To date, 508 salmon sharks have been tagged with M-type dart tags in cooperation with the Alaska Department ofFish and Game on cooperative VIMS cruises.

3b. Age, growth, and demography. When VIMS scientists compared growth rates for sandbar sharks before and after stock collapse from overfishing between 1980 and 1992, they found little growth compensation and no change in the age at maturity. In 2005 the sandbar shark population was sti11less than 50% of that in 1980 and compensation has had more time to become apparent (growth may be affected over more year classes). VIMS scientists continue to examine sandbar shark growth rates (based on vertebral analysis) collected in 2001-2005 for comparison to published historical rates and those derived from archived vertebrae.

VIMS scientists are continuing to work in cooperation with scientists from the University of Hawaii to collect sandbar shark vertebrae from the Hawaiian population which is purported to grow faster, mature younger, and reach a smaller maximum size. Sampling trips were conducted in September 2002, May 2003, September 2003, June 2004, January 2005, and September 2005. These trips have yielded 186 samples for age and growth studies, stomach content analysis, and genetic analysis. 134 sandbar sharks were tagged, injected with OTC, and released for age validation considerations over the time span. Five tagged sharks were recaptured after periods ranging from one week to 17 months. Examination of vertebral centra from these sharks supported the use of vertebral centra for aging sandbar sharks in Hawaii. OTC stained vertebral centra and marginal increment analysis support the hypothesis of annuli formation in the winter months. The age at maturity was estimated to be approximately eight years for males and ten years for females (Romine et al. accepted) suggesting much slower growth rates than previously reported for this population by Wass (1973). Growth coefficients (K) for the Hawaiian population (0.13 yr-1 for males and 0.10 yr-l

for females) were higher than those reported for sandbar sharks in the northwest Atlantic Ocean (0.57 yr-1 sexes combined; Sminkey and Musick 1995) but lower than those reported for Taiwanese waters (0.17 yr-I sexes combined; Joung et al. 2004), although the latter study may have been equivocal.

VIMS scientists continue the process of developing a comprehensive demographic model and stock assessment of the bamdoor skate. During this period, the focus of the work has continued to be on advancing the methodologies of parameter estimation and use the mean lengths of the bamdoor skate populations to re-create the fishing mortality history of the Georges Bank population. We are currently developing the model so that the assumption of constant recruitment, which is commonly violated in real world applications, is no longer necessary. The results of this analysis

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and our earlier work on the life history parameters have been incorporated into these new demographic models. The results of these analyses, combined with the observed recovery from NMFS survey indices, suggest that the barndoor skate has a maximum population growth rate (rintrinsic) of close to 0.45 (slightly lower than our previous estimate, due to the incorporation of recruitment into the model) and is more resilient to fishing pressure than previously believed. A re­analysis ofNMFS survey data also indicates that the recovery of bam door skate populations began in the mid 1980' s, long before the concern about their extinction began. In addition, a final push is underway to finish processing stomach samples, giving insights to the food habits of the species while under the protection of a closed area and during an intensive experimental fishery.

Age and growth studies of deep-sea squaloid sharks are ongoing at VIMS. Due to the vulnerability of deep-sea sharks to fishing pressure, these age and growth data will be crucial for the proper management ofthese long-lived species. VIMS scientists have continued collaboration with Dr. Jose Castro (NMFS, Mote Marine Laboratory) and John Galbraith (NMFS, Northeast Fisheries Science Center) to collect squaloid sharks from the Western North Atlantic and the Gulf of Mexico. Thus far, this collaboration with Dr. Castro and John Galbraith has yielded hundreds of fin spines from 7 different species of squaloid sharks to be used for aging. A third deep-water longline trip with Dr. Castro is planned in the Gulf of Mexico in the summer of 2006. Fin spines were also collected during the MAR-ECO cruise of2004 along the mid-Atlantic ridge to be used for ageing squaloid sharks from this region. VIMS scientists are also assisting Dr. Castro in the finalization of his book 'Sharks of North America'.

VIMS scientists are active participants in the MAR-ECO project (www.mar-eco.no) and continue to work within the MAR-ECO Taxonomy Group to verify the identification of all elasmobranch voucher specimens captured during this cruise. In addition, an annotated list of fish species captured in this region along the Mid-Atlantic Ridge is in preparation. This list will represent the sum work of the MAR-ECO Taxonomy Group and will include any notably rare species, range records and depth records. During the cruise, data were collected (length, weight, sex, maturity) for approximately 5,500 deep-sea sharks (12 species), and fin spines were collected for age and growth analysis from approximately 500 of the squaloid sharks captured (Centrophorus squamosus, Centroscymnus coelolepis, C. crepidator, C. owstoni, Etmopterus princeps, Deania hystricosa, Centroscyllium fabricii). Samples from a few species were also taken for studies of reproductive biology. VIMS scientists will work with Dr. William Hamlett (Indiana University School of Medicine) to process these samples. Specifically, oviducal glands collected from squaloid species will be examined for evidence of sperm storage; also samples were collected from reproductively active female Etmopterid sharks to look for evidence of his to trophy in this species. Several cooperative manuscripts are currently in preparation covering distribution of deep-sea skates and community structure of demersal ichthyofauna.

3e. Habitat and migration studies. During the previous period we re-deployed an array of 19 acoustic receiver stations in Wachapreague Inlet. VIMS scientists also deployed a water quality monitoring device (YSI) to monitor the temperature, salinity, and dissolved oxygen at one end of the array every fifteen minutes throughout the summer months. The receivers were cleaned, and data were downloaded on a weekly to bi-weekly basis beginning in May when the receivers were deployed and continued until the end of October. During the summer of2004, 37 juvenile sandbar sharks were implanted with acoustic transmitters within the array. Two ofthese sharks were caught and killed by a commercial fisherman soon after release, leaving a total of 3 5 sharks with functional transmitters at the end ofthe summer nursery season in 2004. Through 30 June 2005,23 of these 35 sharks (68%) had returned to the array. No additional sharks were detected after this time but 16 of

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the 23 sharks were detected by the array after 01 July. The last shark departed the array on 30 September 2005 and the array was removed in the middle of October.

The coastal lagoons of Virginia provide a source of protection and food for many migratory e1asmobranchs. Previous studies have examined the importance of these lagoons for sandbar sharks as a nursery. Little research has been conducted on the rays that inhabit the region. These lagoons have distinct environmental gradients with regards to sediment types and concurrent fauna, temperature regimes and tidal influences. Habitat use and movements of rays should therefore vary according to the how these variables are manifested in the lagoon. VIMS scientists are currently studying the abundance and distribution ofthe rays that inhabit the region. Specimens were collected using a 22-foot otter trawl pulled by Eastern Shore Laboratory vessels. Wachapreague and Machipongo inlets and the adjacent lagoons were sampled monthly beginning in May (before arrival) and ending in October when sampling indicated the animals had left the lagoons. Sampling was conducted in deep and shallow regions to distinguish depth preferences throughout the lagoon. Shallow areas were defined as regions where water depth is less than 3 meters. Deep areas were defined as channels deeper than 3.5 meters throughout the lagoon region. In July, longlining was conducted to qualitatively examine catch efficiency of the sample gear. Disc width or total length was recorded for all species of e1asmobranchs and te1eosts and sex was determined for all elasmobranchs. Age, growth, diet, and reproductive studies will be conducted on the gymnurid and dasyatid species in the upcoming periods.

Sixty two individuals consisting of seven species of rays were caught trawling. The spiny butterfly ray, Gymnura altavela, and the bullnose ray, Myliobatisfreninvillei, had the highest CPUE (0.005094 number/minute towed) followed by the cownose ray, Rhinoptera bonasus, (0.003502 number/minute towed), the smooth butterfly ray, Gymnura micrura, (0.002229 number/minute towed), the bluntnose ray, Dasyatis say, roughtail stingray, Dasyatis centroura (0.000955 number/minute towed), and the southern stingray, Dasyatis americana, (0.000318 number/minute towed). The spiny butterfly ray, had a higher number caught (0.00598 number/minute towed) in shallow regions than deep (0.00474 number/minute towed), however, the opposite trend was observed in terms of biomass (shallow=0.169 kg/min, deep=0.220 kg/min) possibly indicating size selection with regards to depth. The same trends were seen with the smooth butterfly ray and bullnose ray.

Only qualitative comparisons could be made between longline and trawl gear due to the differences in quantifying CPUE for the respective gears. Longlining occurred in the same area as the trawl sample areas. One kilometer of monofilament was set in both deep and shallow regions. Gangions spaced approximately 20 meters apart were baited with menhaden using circle hooks. Both fishing methods caught essentially the same number of spiny butterfly rays (5 trawling, 4 longlining), and smooth butterfly rays (4 trawling, 3 longlining). However, longlining caught as many bluntnose and southern stingrays (9) as was caught the entire summer trawling (8). This, combined with the frequency of dasyatids caught by hook and line for metabolic work, suggests avoidance of trawl gear by these species. Future plans include longlining throughout the lagoons to quantify ray abundance and distribution as functions of temperature and dissolved oxygen fluctuations.

3d. Shark energetic and osmoregulatory studies. An important aspect of ecosystem-based management is the role of habitat selection. Environmental variables play a key role in the distribution of fishes including elasmobranchs. Examining catch rates of elasmobranchs with respect to various physical variables should give an indication of the environmental conditions they prefer. Various studies have examined how parameters such as temperature, salinity, depth and dissolved

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oxygen content affect the distribution of elasmobranchs. Often ignored in these analyses is the underlying physiology that dictates the animal's distribution. Organisms residing in dynamic environments must be able to alter their physiology in response to these changes or leave the area. Animals that conform to the changes presumably will require a shift in the energy allotted to sustain their life at rest (Standard Metabolic Rate = SMR). Measuring the SMR during shifts in these variables should give an indication of the stress associated with adapting to environmental changes. The initial SMR was measured for the spiny butterfly ray, Gymnura altavela, and the bluntnose ray, Dasyatis say. The average SMR of the bluntnose ray (146.04 mg021hrlkg) was twice as high as what was observed in the spiny butterfly ray (71.63 mg021hrIkg). Future plans include examining how the SMR of these animals responds to changes in salinity, temperature, and dissolved oxygen content and relate it to observed distribution and abundances seen in the longline data.

During summer months, juvenile sandbar sharks inhabit regions of the Chesapeake Bay that have salinities down to approximately 20. We hypothesize this represents a physiological barrier against predation by larger sharks that are unable to use these lower salinity waters. During this research period VIMS scientists conducted experiments designed to quantify the osmoregulatory abilities of these sharks. Juvenile sharks (1.52 - 2.23kg) were kept in three closed system aquariums and the salinity was decreased at predetermined weekly intervals (from 33 to 27 to 20) by addition of fresh water. The sharks were weighed and blood samples taken once per salinity treatment. Hematocrit, hemoglobin, red blood cell count, total protein, plasma osmotic pressure, pH, pC02, p02, sodium, potassium, chlorine, urea, lactate, and glucose concentrations were measured from each sample. After one week at 27ppt, the following changes were observed: 5.7% decrease in hematocrit, 7.6% decrease in total protein concentration, 7% decrease in plasma osmotic pressure, 21.8% decrease in plasma urea concentration, 3.6% decrease in plasma sodium and average weight (kg) increased 2.3%. At 20ppt, the following changes were observed: 8.7% decrease in hematocrit, 6.6% decrease in hemoglobin, 16% decrease in total protein concentration, 14% decrease in plasma osmotic pressure, 5.3% decrease in plasma sodium content and 49% decrease in plasma urea concentration. The sharks' average weight (kg) increased 7%. No significant changes in plasma glucose, potassium, chlorine and lactate were evident. These data suggest the sandbar sharks are coping with the osmotic stress by maintaining plasma ion levels in spite of an increase in their extracellular water content.

3e. Sandbar shark genetics. VIMS scientists continue to work on estimating the effective population size of sandbar sharks using the Chesapeake Bay nursery, as well as the effective number of females pupping in these nurseries, using modem genetic techniques. This study will also examine the possibility of significant loss of genetic variation during the last thirty years of exploitation by comparing gene frequencies between museum samples collected in the late 70's with samples collected in the last several years. Work is also being done to compare gene frequencies of animals caught in the Chesapeake Bay nurseries with those found in other nurseries along the east coast to examine philopatry and estimate gene flow. Periodicity is being assessed within nurseries by using highly polymorphic loci to detect YOY kin groups within and between sampling years. In order to accomplish these goals, over 800 fin clips have been taken from juvenile and adult female sandbar sharks in the Eastern Shore and lower Chesapeake Bay nurseries with an additional 250 samples from Delaware Bay. Six microsatellite markers have been designed at VIMS. Cross species amplification has demonstrated the utility of these markers for other carcharhinids. In addition, two other micro satellite markers from the literature have been optimized to ensure efficient, accurate genetic screening. Two pregnant females caught on Virginia's Eastern Shore lagoons and their litters were screened at these eight loci. The first litter contained 11 pups and a minimum of four sires was

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necessary to explain the observed gene array. The second litter contained seven pups and a minimum of two sires was necessary to explain the observed gene array. In addition, a YOY sandbar shark caught in 2003 was identified as the progeny of an adult female caught in the same Eastern Shore Lagoon in 2005 using relatedness software. Fourteen additional mother/litter groups were genotyped to examine the prevalence multiple paternity in sandbar sharks throughout the western North Atlantic. Of the sixteen litters examined, fourteen showed evidence of multiple paternity. The number of estimated sires per polyandrous litter varied from 2 to 5. The control region has been sequenced for 48 YOY sharks from Chesapeake Bay and 48 sharks from Delaware. Samples of YOY from Georgia, South Carolina and GOM will be added in the next year enabling us to estimate the female effective population size and define the nature of gene flow between nurseries. Sequencing YOY samples from other locations worldwide will begin in the coming months enabling us to examine phylogeography and gene flow ofthe species

3f. Publications and conferences. During this period VIMS research was presented during three major scientific conferences. Nine presentations (7 oral, 1 poster, 1 co-authored) were made during the combined annual meeting of the American Society ofIchthyologists and Herpetologists and the American Elasmobranch Society in Tampa, FL. Three presentations (1 oral, 2 coauthored) were made at the Annual meeting of the American Fisheries Society in Anchorage, AK. One coauthored presentation was given at the meeting of the European Elasmobranch Association in Monaco. VIMS biologists published four papers and one book chapter and co-edited three books and one conference proceedings in the peer-reviewed literature during this period.

University of Florida Report (G. Burgess, P/I)

4a. Fishery independent sampling of commercially exploited sharks. Fishery independent long­line sampling was conducted aboard leased commercial shark fishing boats in the summer of2005. Inclement weather and vessel availability limited the number of sea days of the FPSR. Nonetheless, FPSR scientists were at sea 8 days in June, August and September in the southeastern Gulf of Mexico and in the Atlantic off the coasts of the Florida peninsula. A total of206 sharks were caught on these expeditions. The dominant species in the catch were Atlantic sharpnose shark (117), nurse shark (34), and tiger (24). Some of these sharks were tagged and released alive, others, primarily those that arrived at the boat dead or moribund, were necropsied and completely "worked up" to provide tissues and materials for biological studies by FPSR scientists and NSRC collaborators. Data and specimens derived from our fishery independent surveys have contributed to our ongoing biological studies of age, growth, and reproduction (see item 4b).

We have continued to collect biological samples for collaborators in NMFS and other NSRC institutions. We have provided bull shark vertebrae for age and growth studies being done at the NMFS Narragansett labs, as well as bull shark muscle samples to scientists in state agencies studying heavy metal concentrations in fish tissues.

Specimens taken during our surveys have also contributed to an ongoing study on shark jaw morphometrics. In collaboration with scientists at the University of South Florida, we are gathering morphometric data from carcharhinid, sphyrnid, and larnnid jaws and teeth. The project goal is to provide a means of accurately discerning the approximate size and species of a shark by statistically analyzing measurements from a bite impression. This study includes data on more than one hundred

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and fifty specimens of twenty different species, including tiger, bull, and white sharks.

4b. Studies of the age, growth, and reproduction of commercially important sharks.

4b 1. Age and growth ofthe Great Hammerhead Shark (Sphyrna mokarran). During this reporting period we finished processing vertebra samples for this project and began our analysis. We have analyzed vertebrae from 179 specimens ranging in size from 60 to 320 centimeters fork length. Preliminary results indicate that this species may grow at a faster rate than S. lewini and attain an older maximum age (48 years old). In the next reporting period we will complete this project and present the finding at a research conference. We also anticipate submission of a manuscript for this project this year. This study will be the first to provide growth data for this poorly known species.

4b2. Reproduction o{the sandbar shark (Carcharhinus plumbeus). During this reporting period we began analysis of the gross morphology of sandbar shark gonads and reproductive tracts. Analysis has been completed for 654 'specimens (383 females and 271 males) collected in the northwest Atlantic Ocean and eastern Gulf of Mexico. During the next reporting period we will complete the gross morphology observations, produce gonadosomatic indices for both sexes, and begin histological analysis of components of the reproductive tracts. We will also continue to collect specimens to fill any temporal gaps in the data set.

In a collaborative effort with NSRC colleagues at VIMS, we recently completed a study investigating the presence of multiple paternity in the sandbar shark. Litters (n= 16) were genetically analyzed to determine if polyandry was present. Polyandry was detected in 14 of the 16 litters suggesting that this strategy is common for this species. A manuscript and presentation of these paternity data will be completed in the next reporting period.

4b3. Reproductive biology ofthe blacknose shark (Carcharhinus acronotus). The reproductive periodicity of blacknose sharks, Carcharhinus acronotus, has been completed for specimens collected in the Northern Gulf of Mexico. Monthly changes in shell gland weight, right ovary weight and ovarian follicle diameter were assessed for 74 mature females. Temporal changes in testes weight, testes width and percent of mature spermatocysts were examined for 64 mature males. Trends in female reproductive tissues suggested an annual peak in reproductive activity during June and July, while trends in male parameters suggested an annual reproductive peak during May and June. Although male and female reproductive activity peaked in different months, a strong synchronicity existed between the percent of mature spermatocysts and the diameter ofthe largest ovarian follicle. Based on these results, the mating season ofblacknose sharks lasts from mid May to July in the Gulf of Mexico. Maximum embryo sizes were observed in May which suggested that partition occurs during late Mayor early June. Results indicate that blacknose sharks have a clearly defined annual cycle in the Gulf of Mexico. This conclusion is further supported by the complete absence of gravid females without vitellogenic ovarian follicles among all mature females examined. This information is currently in peer review for publication in the Journal ofFish Biology and will be presented at this years American Elasmobranch Society meeting.

4b4. Shark embryo fitness. We are continuing with the collection of litters for this study. Our fishing efforts were severely curtailed during this reporting period do to inclement weather. We plan to have enough samples from the Atlantic sharpnose shark to begin analysis by the end ofthe next reporting period. Preliminary results from weighed sandbar shark litters indicate the occurrence of runts in some litters. We will further investigate this phenomenon during the next reporting period.

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4c. Studies of skate life history.

4cl. Age. growth. and reproduction o(the roundel skate (Raja texana). Scientists at the FPSR have completed analyzing the age, growth and maturity of the roundel skate from 231 specimens ranging in size from 277 to 630 mm total length (TL). Using vertebral band counts, the oldest age estimates obtained for the roundel skate were 8 years for males and 9 for females, which corresponded to total lengths of 495 mm and 630 mm, respectively. Age bias plots and coefficient of variation suggests that our ageing method represents a non-biased and precise approach to age assessment. Marginal increment and edge analyses suggests that growth bands are formed annually with a distinct trend of increasing growth at the beginning of March. Back calculations suggested a birth size of 113-118 mm TL. Growth was assessed using three models: the von Bertalanffy (VBGM), the von Bertalanffy with size at birth (VB with Lo), and the Francis model. Male and female growth was significantly different. The VBGM and Francis model predicted the same growth for males (k = 0.228) and females (k = 0.228), however the size at birth was underestimated using these models due to the paucity of 0-1 year olds. Maturity occurred at about 444 mm TL and 5.0 years for males, while females matured at about 534 mm TL and 5.8 years. This information is currently in peer review for publication in the Journal of Marine and Freshwater Research.

We are currently collecting tissues to examine the reproductive cycle for this species. However, our current reliance on samples taken as bycatch from the seasonal trawl and from NMFS bottom trawl surveys fishery will make it impossible to attain this goal in the upcoming budget year.

4c2. Steroid hormone analyses and the reproductive cycle o(two exploited skate species. As part of ongoing collaborative projects, FPSR scientist Sulikowski has been examining the life history of two exploited skate species from the Gulf of Maine. The smooth skate, Malacoraja senta, and thorny skate, Amblyraja radiata, are two sympatric batoids whose stocks are at or below threshold levels within the Gulf of Maine. During the past five years, a large life history study was conducted in an attempt to accurately describe important biological life history parameters previously lacking for these species. As part of that project, the goal of the current study was to gain insight into the reproductive biology of these species. Plasma samples were obtained from mature smooth and thorny skates of both sexes captured all months of the year, and the Estradiol (E2), Testosterone (T), and Progesterone (P 4) concentrations were determined using radioimmunoassay (RIA). The respective steroid hormone concentrations were averaged, compared to morphological reproductive parameters, and plotted to examine any monthly trends. Based on morphological parameters, each species exhibited an annual reproductive pattern. However, preliminary analysis indicated that E2 concentrations in females may be different between the two skate species over the course of their reproductive cycles. Analyses ofthe other steroid hormones in female and male smooth and thorny skates are currently underway so that we can compare the respective plasma profiles during their reproductive cycles. This information will be presented at this years American Elasmobranch Society meeting.

4d. Tagging and sonic tracking of sharks and rays in Indian River Lagoon (IRL). During the report period, a total of four bull sharks were captured in the Indian River Lagoon using longline and rod and reel sampling. These sharks ranged in size from 72 to 80 cm total length. Three of these young-of-the-year sharks were actively tracked, yielding a total of34 hours of short-term movement and habitat use data. This concluded the manual tracking portion of this study in which lObulI sharks were tracked for a total of 140 hours. An array of 19 passive listening stations was maintained

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within the IRL system in conjunction with the Dynamac Corporation at the Kennedy Space Center. During the report period an additional seven receivers were purchased by this program and

one additional receiver was purchased by Dynamac Corporation. These eight receivers and the original 19 receivers stationed in the IRL will be deployed and concentrated in the Mosquito Lagoon portion of the IRL within the next three months. During the report period, 30 additional transmitters were purchased and will be placed on ray species within the study area by June of2006. Netting and longline sampling will commence in February of the next period and rays of four species will be captured and tracked using the passive array system: spotted eagle rays, Aetobatus narinari, cownose rays, Rhinoptera bonasus, bluntnose stingrays, Dasyatis say, and smooth butterfly rays, Gymnura micrura. In addition any neonate or juvenile bull sharks captured within the area during normal sampling operations will be outfitted with acoustic transmitters and tracked using the passive listening array.

4e. Age-structured simulation model for the dusky shark. During this reporting period, two age­structured fisheries assessment models were selected for final use in this project. Colerain utilizes a Bayesian framework, which allows for prior information to be incorporated and uncertainty around estimates to be assessed from the Bayesian posteriors. The model allows for temporal changes in the selectivity of the fishing fleet and catchability of the fishing fleet, survey selectivity modeled as age or size based, simultaneous fitting oflength and age data, and robust normal likelihood functions for proportions. After fitting the model, policy evaluation (reported as Bayesian priors) can be completed by looking at different harvest strategies on any statistic of interest. In the SCS age­structured model, multiple fisheries, gear types and selectivities can be modeled and detailed biological information can be incorporated into the model. Population dynamics are modeled through an age and sex structured simulation approach. The model is fitted using observed catch rates of fishery independent surveys and comparing this to the population level within the model. Catch rate data is assumed to be proportional to biomass and catch rates are compared to the exploitable biomass of specific survey gear. The model can be used to provide estimates of the current status of the species and to analyze the impact varying harvest strategies would have on future populations.

Data has been collected from the following sources: National Marine Fisheries Service (NMFS) South East Fisheries Science Center (SEFSC) quota monitoring system, the Northeast and Southeast regional general canvass landings, the Virginia Institute of Marine Science (VIMS), the Commercial Shark Fishery Observer Program (CSFOP), Large Pelagic Survey (LPS), Pelagic Longline Observer Program, Marine Recreational Fisheries Statistic Survey (MRFSS), NMFS Headboat Survey (HBOAT) and Texas Parks and Wildlife Recreational Fishing Survey (TXPWD). Communication with colleagues outside ofthe FPSR and site visits to collect data have continued throughout this time period.

4f. Maintenance and growth of the International Shark Attack File (ISAF) and public education about shark attack. A total of 59 new case files were entered into the ISAF database during this time period and a total of91 cases were updated with new information. Staffbegan a project to update and improve the existing ISAF database. This included hiring a computer technician to aid in the development and implementation of the new database. Once this project is completed, all of the existing case files will be moved into an user-friendlier web-based interface. Staff also continued the long-term project of double checking every hard case file against the database to check for accuracy in data entry and standardization. Case files that have been open for more than 6 months were re­visited and victims were again contacted for further information. Requests for information from the

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public, media and scientific communities were continuously provided. The ISAF web pages continued to be the most heavily visited of all pages on the FLMNH web-site.

4g. Public education and web site. The FLMNH Ichthyology Division web pages, including the FPSR web pages, received 66,734,697 "hits", 2,596,428 visits, and 1,980,255 unique visitors during the reporting period. Materials relating to elasmobranchs on the site have been expanded and improved. New elasmobranch species accounts have been added to the "Biological Profiles" section. To date, we have a total of 92 elasmobranch profiles available online. Also, the image gallery has been expanded with new submissions from photographers. The "In The News" shark pages are updated daily with the latest news releases on research and conservation related to elasmobranchs.

The IUCN Shark Specialist Group (SSG) and AES web sites have been continually upgraded and expanded. This includes news stories for each IUCN SSG region as well as features on the activities ofthis group. Maintenance ofthe AES web site consists primarily of posting new meeting information as well as updating the membership directory, posting meeting minutes, and adding AES newsletters as they become available. The "Education" web page now includes a Most Commonly Asked Sawfish Questions section that answers questions regarding sawfish basics, biology, conservation, and research. Ongoing maintenance activities continue to include every section of the shark web site including organizational information, news stories, image gallery, education, conferences and meetings, staff, outside links, and references. Over the next reporting period, the web site will continually be expanded with the addition of new information in appropriate sections.

4h. Classroom-based elasmobranch education initiatives.

4h 1. Project Shark Awareness. Project Shark Awareness is a classroom-based outreach program for educating school teachers and environmental educators about the myths and realities of shark behavior, biology, and conservation. This program consists of a series of workshops and training sessions augmented by a variety of teaching support materials, including a teaching kit consisting of a PowerPoint presentation, teaching guide, handouts, methods to evaluate student learning (quiz, puzzles, question sheets). In addition, shark jaws, teeth, skin, and fossils in the teaching kits provide hands-on learning opportunities. A companion web page within the FLMNH Ichthyology education web site is available online to accompany Project Shark Awareness materials.

Over the reporting period, three Project Shark Awareness workshops for secondary school educators were held at the FLMNH. Funded by the Disney Wildlife Conservation Fund, these workshops reached 37 educators, further increasing the exposure of this program throughout the state of Florida. Teaching materials continue to be updated, expanded, and improved based upon comments from participants.

4h2. Sawfish In Peril. Sawfish in Peril, a new classroom-based education initiative, is currently being designed and will be implemented in a manner similar to Project Shark Awareness. Very little is known about sawfishes, which historically were very abundant in the tropics. Today, the U.S. distribution of the smalltooth sawfish (Pristis peetinata) is primarily restricted to the waters off the coast of southwest Florida. Although it is difficult to estimate the exact numbers of sawfish remaining in U.S. waters, it is likely that the population has declined at least 95% over the past century. As a result, the smalltooth sawfish has recently been listed for protection under the U.S. Endangered Species Act. The largetooth sawfish (Pristis peroUeti), once found in low numbers in waters ranging from Texas to Florida, probably has been extirpated from U.S. waters. Sawfish In Peril will result in a better informed public concerning the plight and protection of sawfishes native

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to u.s. coastal waters, as well as the fate of sawfishes in general, which as a group are globally threatened.

Dependent upon external funding sources, one-day workshops will be held at the FLMNH for educators throughout the state of Florida. At this workshop, participants will receive a teaching kit, attend lectures and multimedia presentations, and participate in hands-on demonstrations to enhance their understanding of sawfish. The teaching kit, which is currently being developed, will contain a multimedia presentation, teaching activities, sawfish species bioprofiles, and other educational materials. The teaching kit will be an effective tool for each educator in developing educational initiatives at their representative facilities. A companion web site is currently being developed for the Sawfish In Peril program. This web site will be an integral segment ofthe program and will be available online within the Florida Museum of Natural History Ichthyology education web site. The web site will allow educators to access supplemental information and new or revised teaching materials as they are posted. These materials will also include up-to-the-minute biological and conservation information, sawfish in the news, and listing documents, along with links to appropriate web sites such as the Sawfish Recovery Team and sawfish research programs within the NSRC and elsewhere.

4i. Responses to requests for data, analysis, and technical information. The staff of the FPSR, especially those involved with the International Shark Attack File, have been busy responding to requests for information during the reporting period. We have handled 956 individual correspondences (email, phone, or postal mail) with various organizations, news agencies, scientists, and lay individuals asking for information and analysis on matters related to sharks and rays, especially shark attacks and related issues, shark ecology and biology, and shark conservation and fisheries. These requests have come from all over the world. FPSR staff members have also responded to numerous requests for interviews and for information on sharks from the general public, especially students. We have provided tissues, specimens, and information to collaborating scientists working in many different organizations as follows: NMFS labs in Panama City and Narragansett, NMFS Office of Highly Migratory Species, Dynamac Corporation at Kennedy Space Center, Florida Fish and Wildlife Commission, Wildlife Conservation Society, and collaborators in the NSRC program at the Center for Shark Research, MML. Two NMFS departments, the Protected Resource Division and the Highly Migratory Species Division, requested data and information, and these requests were addressed. We also provided technical support and tissue samples to support ongoing studies on various aspects of shark biology by scientists in South Africa, Rhode Island, and Florida.

4j. Publications, materials, and conferences. During the reporting period, FPSR personnel are authors or co-authors on eight papers accepted for publication and in press. Several manuscripts have been submitted and are under review and several others are nearing submission. Project personnel gave five posters and eight oral presentations on elasmobranchs at scientific meetings and professional conferences. We attended and were actively involved in nine meetings, conferences, or workshops relating to elasmobranch issues. We were especially active in support of Project Shark Awareness and with the Center for Ocean Sciences Education Excellence (COSEE) program. We presented a workshop to NMFS commercial shark fishery observers to train them in taking biological samples while at sea.

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Respectfully submitted,

Robert E. Rueter, Ph.D. Project Coordinator & Director, Center for Shark Research, Mote Marine Laboratory FEBRUARY XXXXX 2006

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