Penguin ConservationJuly, 1995 vol. 8, no. 1

In this issue

Announcements & Inquiries 2

Breeding and Rehabilitation of African Penguins 3

The Humboldt Penguin Species Survival Plan of Japan 4

Causes of Sickness and Injury in Little Penguins 6

Sharks in the Galapagos 13

Penguin Populations in the Falkland Islands 14

From the EditorArtificial nests for wild penguins?

An article in this issue (page 20) re­ports on the successful use of an artificialnest burrow structure (partially buriedPVC pipe) in a colony of African penguins.Other institutions use similar structures.We would like to promote practical dis­cussion on ways of providing cheap,easily installed artificial burrows to wildcolonies of Spheniscus penguins in loca­tions where populations are threatenedand where lack of protected nest sites maybe a limiting factor.

Financial supportThanks to the many readers and insti­

tutions who responded to the request, inour last issue, for financial contributions.We have also received a generous grantfrom the Portland Chapter of the Ameri­can Association of Zoo Keepers. Thissupport is paying the printing bill, whileadditional sources of money are beingsought. Contributions are welcome at anytime; please see back cover for details.

Summer 1995 issueThe next issue will contain some mate­

rial now in hand for which there was notspace in this issue, including notices of re­cently produced studbooks, a finalsummary of the immediate impact of the'Apollo Sea' oil spill on African penguins,and Directory corrections/additions.

QueriesDegenerative Joint Disease

Three individuals in the 35-memberHumboldt colony at the Metro Washing­ton Park Zoo show signs of severe chronicdegenerative joint disease involving thestifles and coxo-femoral joints. All indi­viduals are related. The collection appearsquite healthy otherwise with no otherknown medical problems.

Veterinarian Dr. Mitch Finneganwould be interested in receiving informa­tion from anyone who has seen thisproblem, whether in related or unrelatedpenguins. Please contact him at:

Metro Washington Park Zoo4110 SW Canyon Rd.Portland, OR 97221 USAfax 503-226-0074

2

CorrectionsThanks to JAZGA

The article written by Mr. Yamazaki etal. which appeared in Penguin Conservationvol. 7, no. 3, November 1994, on sex deter­mination of the Humboldt Penguin, wasoriginally printed in the Journal of the Japa­nese Association of Zoological Gardens andAquariums vol. 33, no. 4, 1991. The articlewas translated and reprinted with the per­mission of the authors and the JapaneseAssociation of Zoological Gardens andAquariums GAZGA).

We regret that this notice was inadvert­ently omitted when the translated articlewas printed, and extend our thanks toJAZGA and the article's authors for theirpermission to reprint it.--­Penguin CAMP

The November 1994 issue contained anarticle by Dr. John Croxall concerning the 1992Penguin Conservation and Management Plan.The following paragraph, summarizing workunder way since the 1992 Penguin CAMP, hadbeen received from Dr. Susie Ellis ofthe CaptiveBreeding Specialist Group, and should have ap­peared in the November issue to provideadditional information on this subject.

"A Penguin CAMP Review Workshopwill be held in conjunction with the Third In­ternational Conference on Penguins inSouth Africa the first week in September1996. Development of a data set for use atthat workshop, prepared collectively bypenguin biologists worldWide, is underway.Oversight responsibility for the workshopwill be shared by Drs. John Croxall, JohnCooper, andSusie Ellis. At this second work­shop, a consensus CAMP document will bedeveloped with full participation by pen­guin biologists."

Queries

"101 systemsInformation on use of hydrogen perox­

ide in water purification systems forpenguin exhibits, is being requested by:Simon Wakefield, BiologistMarwell Zoological ParkColden Common or WinchesterRants 5021 1JHGreat Britain fax 0962-777511

AnnouncementsMarine OrnithologySpecial Offer for New Subscribers

For double the cost of the normal 1995subscription to volume 23 of Marine Orni­thology, new subscribers will also receivefive years of back numbers (vols. 18-22,1990-1994). Marine Ornithology is the onlyinternational, fully refereed journal dealingsolely with seabirds, and thus should be onthe shelves of all marine ornithologists.

Payment should be made in the nameof the"African Seabird Group" and sent toPO Box 34113, Rhodes Gift 7707, SouthAfrica.

Rates: personal subscription, US$60 orUK Sterling £40; institutional subscription,US$90 or UK Sterling £60.

Most earlier back numbers are also avail­able; direct enquiries to the above address.

(Received from John Cooper,Editor, Marine Ornithology.)--­African Penguin Studbook

The 1993 African Penguin (Spheniscusdemersus) North American Regional Stud­book has been published through TheBaltimore Zoo. The living population ofAfrican Penguins in North America was631 individuals (161.172.298) as of 31December 1993, in 42 institutions. Thepopulation showed a 6.94% increase overthe 31 December 1992 population. Con­tinuing with the importance of bettercaptive management, a petition for anAfrican Penguin Species Survival Plan isbeing drafted through The Baltimore Zoo.The 1994 African PengUin RegionalStudbook is being compiled and will beavailable as soon as possible through TheBaltimore Zoo.

(Received from Steven J. Sarro, Stud­book Keeper, The Baltimore Zoo, DruidHill Park, Baltimore, MD 21217 USA; fax410-396-3829.)

Short NotesMasses of dead Pacific sardines are

washing up on Australia's southern coastas a result of what experts say is likely avirus or tropical disease. The fish plague isfeared to have kiilled billions of pilchardsalong 2000 miles of coast from Perth toSydney. [The Oregonian, May 25, 19951

Penguin Conservation July 1995

Breeding and Rehabilitation of Blackfooted Penguins(Spheniscus demersus) at the East London Aquarium, South Africa

WILLIE MARITZ

East LondonPOrt~/QqJ..

U6/ ~~\ Bira Island

Plettenberg Bay Algoa Bay

Figure 1. Artificial nest burrow.

after a period of time, has enabled theAquarium to maintain a group ofpenguins for study and exhibit purposes,and provide captive-bred penguins forapproved zoological institutions else­where, with minimal impact upon thewild population.

Should any institution be interested inacquiring some of these captive-bredpenguins, or in learning more about howto furnish enclosures to facilitate success­ful breeding, the Aquarium may becontacted at the follOWing address:

The DirectorCultural and Environmental

ServicesP.O. Box 984East London 5200

Attention: Aquarium Curator ..

/. • Cape Tow_n.r-..___­

Dassen Island

covery (after being flipper-banded to keeptrack of their movements), or, in the caseof a few individuals, placed into theAquarium's breeding colony. The pen­guin colony at the Aquarium consistsentirely of rehabilitated adult birds.The majority of these birds (95%) arereleasa ble, and after a period in the colonythey are returned to the ocean, andreplaced with other individuals. In thisway maximum genetic variability ismaintained, and birds are not removedpermanently from the wild. Unreleasablebirds (missing a flipper or an eye, etc.)constitute the remaining 5% of the colony;they also pair up and breed. The presentcolony contains 9 breeding pairs, whichraise an average of 20 chicks per year. Toprevent possible in-breeding, the chicksare surplused as soon as they are able tofeed independently. In recent years cap­tive-bred penguins from this colony havebeen exported to various reputable centersin the U.S., Europe, and the Far East.

The penguin enclosure at the Aquariurn

resembles Bird Island in virtually everyrespect. Vegetation in the form of wildspinach was imported from Bird Islandfor the penguins to use in nestconstruction. In place of penguin-dug bur­rows, however, man-made nesting sitesare provided by means of 500 mmdiameter PVC piping dug into anembankment (see Figure 1). This preventsflooding of the nests and protects theeggs and young chicks from the ever­present gulls.

The precarious position of the Africanpenguin was highlighted recently with themassive oil-spill at Dassen Island.The East LondonAquarium plays avital role in rehabili­tating and releasingpenguins along theeastern coastline.The successful addi­tion of a breedingcolony, whose mem­bers are 'rotated out'

Willie MaritzAquarium CuratorEast London AquariumEast London, South Africa

The City of East London is situated ona stretch of sub-tropical coastline on theSouth-African eastern seaboard. Some 150km southwest of East London, lies Bird Is­land, the northernmost natural habitat ofthe African or Blackfooted Penguin Sphe­niscus demerslIs. Bird Island is hostile froma human point of view-very flat, wind­swept, and exposed-but it providesnesting sites not only for a colony of about5000 penguins, but also for a colony ofCape Gannets (Sula capensis). About 30%

of the island's surface is covered with fos­sil guano, punctuated by rocky outcrops.The penguins dig into the guano to makenest burrows, and furnish their nests withthe dried leaves and stems of a species ofwild spinach (Mesembryanthermum aitonis)which grows on the island.

The natural feeding range of the BirdIsland penguins extends to the northeastup to East London and westwards downto Plettenberg Bay. During the month ofMay each year, thousands of gannets andpenguins follow the "sardine run" north­wards up along the coast. The denselypacked schools of Sardinops ocellatus areutilized by all piscivorous predators, in­cluding penguins.

Sick and injured penguins comeashore on a regular basis in the East Lon­don area. These birds are then brought tothe East London Aquarium for medicalattention, rehydration and rehabilitation.Since its founding in 1931, the Aquariumhas served as a rehabilitation center forthis species. The most common causesleading to admission and rehabilitationinciude oil contamination, shark bite inju­ries, nylon and plastic entanglement, anddehydration.

Since 1989, 203 penguins have beenadmitted. Of these, 54 (26.6%) died of theirinjuries or were euthanized; the remaining149 (73.4%) were either released upon re-

Penguin Conservation July 1995 3

Captive Management Programs: Japan

The Humboldt Penguin Species Survival Plan of Japan

The Humboldt Penguin Species Sur­vival Plan of Japan (SSP]) wasestablished in 1991. Yarious data havebeen collected since 1992 and the stud­book was established in 1993. OnSeptember 8, 1994, the first committeemeeting was held at Tokyo Sea LifePark.

This report summarizes the currentsta tus of the Humbold t Penguin in Japanand the result of the committee meeting.

Infonnation on status anddevelopments in the Japanesepopulation in 1993

1) Population sizeThe total number of registered living

individuals is 971 (213.214.354 [213male, 214 female, 354 unknown]) in 72institutions. There are 12 institutionswhich each have more than 19 individu­als, 25 have between 10 and 19, and 35have fewer than 10. At the two extremes,the largest population consists of 90 in­dividuals (in Niigata City Aquarium)and the smallest populations (at threedifferent institutions) each consist ofonly a single individual.

2) FoundersJapanese zoos and aquaria often de­

pend upon animal dealers when addingto their collections. Animal dealers areunwilling to tell the source of the ani­mals they sell; consequently, the originof animals purchased from animal deal­ers is often unknown. Origin-unknownor foreign captive-bred individuals aretreated as founders. There are 190 livingfounders or potential founders in Japan(90.60.40).

Hidemasa HoriHumboldt Penguin Species Coordinator,

SSCJIlAZGATokyo Sea Life ParkTokyo, Japan

4

Tokyo, Japan

3) Fecundity and mortality from Jan. 1to Dec. 31, 1993

The number of registered living indi­viduals was 897 on Dec. 31,1992. Therewere 152 hatches and 96 deaths from Jan.1 to Dec. 31, 1993. The fecundity is 16.9%and the mortality is 10.7%, yielding agrowth rate of 6.2%. This figure shows theentire Japanese population is expanding.However, there was breeding at only 28institutions; in 18 of them, fecundity ex­ceeded mortality. At 44 institutions, no .breeding took place.

Only a comparatively small number ofindividuals were successfully breeding,and accounting for the growth in popula­tion. Not all of these individuals are ofhigh breeding priority. These are prob­lems from a genetic point of view.

Problems and recommendations

1) HybridsIt was pointed out at the Penguin

CAMP meeting in New Zealand, in 1992,that hybridization might be occurringamong Spheniscus penguins in Japan.Unfortunately, there are a few hybrids inJapan but they are identified and notallowed to breed. According to my data,no other hybrids are indicated in thehistorical records. There are 21 institutionswhich house Humboldt Penguins andalso house Magellanic Penguins, AfricanPenguins, or both, in the same space, buthybridization is prevented. Isozymeanalysis of blood samples byelectrophore­sis is being carried out to verify this.

For complete prevention of hybridiza­tion it is necessary to separate eachSpheniscu5 species. An institution which

HIDEMASA HORI

houses two or three species in the sa mespace should separate them. If no suitablespace for additional exhibits exists in agiven institution, then one species shouldbe kept and the other species transferredto another institution.

2) Individual identificationMost institutions use flipper bands,

with good success. However, sometimesbands are removed when birds are trans­ferred, and the identity of the individualsis in doubt.

To follow individuals through translo­cations, it is necessary to identify themcompletely and consistently. In the case ofa transfer, the flipper band should neverbe removed by the sending institution,and the identification card should accom­pany the bird to the new institution. Ifpossible, the transponder system(TROYAN) should be used from now on.

3) Goals for the next five yearsThe present situation in Japan is not

adequate for conservation of the captivepopulation of Humboldt Penguins. Eachinstitution manages its population by itsown policy. At a number of institutions,policy is based only upon maintainingtheir own exhibit population, withoutconsidering the preservation of geneticdiversity in the entire Japanese pop­ulation of this species.

Although it is no longer permissible todepend on captured birds from the wild tomaintain exhibit populations, unplannedand unrestricted breeding of captive ani­mals is not in the best interest of thecaptive population. It is essential thatsome core populations are established ininstitutions which have suitable policiesand conditions for captive breeding.

The target for the next five years is theestablishment, in such institutions, ofsome core populations consisting of theindividuals having high breeding priori­ties. The long-term breeding program willbe based upon these core populations

Penguin Conservation July 1995

After that, the institutions which havethe core populations will be allowed toparticipate in the breeding program of theHumboldt Penguin SSP}, and the other in­stitutions will house individuals notneeded for the breeding program.

4) Infonnation on the organization ofthe Humboldt Penguin SSP}

1) Species Coordinator and StudbookKeeper

Hidemasa HoriTokyo Sea Life ParkRinkai-cho 6-2-3Edogawa-ku, Tokyo 134

2) Species Committee

Mitsuru WatabeOtaru AquariumShukutsu 3-303Otaru-shi, Hokkaido 047

Yukio YamazakiNiigata City AquariumNishifunami-eho 5932-445Niigata-shi, Niigata 951

Kazuyoshi ItohVeno Zoological GardensVeno kohen 9-83Taitoh-ku, Tokyo 110

Kohki MorikakuNogeyama Zoological Gardens of

YokohamaOimatsu-cho 63-10Nishi-ku, Yokohama-shi, Kanagawa

220

Hiroyuki FujieKyoto Municipal ZooOkazaki Kohen nai, Okazaki hohshoji­

cho

Sakyo-ku, Kyoto-shi, Kyoto 606 •

Penguin Conservation July 1995

Age

29 X

d": N=458 28 X ~: N=432

27

X 26

25 X

X 24

23 X

XX 22 X

XXX 21 XX

X 20

XXX 19 XXX

XXX? 18 ?XXX

X? 17 ?

X? 16 ?XX

XXXXX 15 XX

XXX 14 X

X? 13 ?XX

XXXX? 12 ?XXX

X? 11 ?XXX

XXXXX? 10 ?XXX

XXXX? 9 ?XXXX

X? 8 ?XX

XXXXX? 7 ?XXXX

XXXXXX? 6 ?XXXXX

XXXXXXXX?? 5 ??XXXXXXXXXXX

xxxxxxxm 4 mxxxxxxxxxxxXXXXXXXX????? 3 ?????XXXXXXX

xxxxxxx????????? 2 ?????????XXXXXX

XXXX??????????????? 1 ????????'?7????XXX

X??????????????? 0 ???????????????

84 72 60 48 36 24 12 Number 12 24 48 60 72 84

Figure 1. Age distribution and sex ratio. X == sex known, ? == sex unknown. With regard toage, there are 81 individuals ofunknown age, ofwhich 31 are male, 28 female, and 22 ofunknown sex.

5

Causes of Sickness and Injury in Little Penguins (Eudyptula minor)

Rehabilitated at Phillip Island, Victoria, AustraliaWENDY A. D'AMORE

AbstractBetween July 1984 and June 1992,670

juvenile and adult Little Penguins werereceived a t the Penguin and KoalaRehabilitation Complex located at thePhillip Island Penguin Reserve. Of these,295 were successfully rehabilitated andreleased. The majori ty of birds were fOlUldon the island (60.4%). Other importantareas were Port Phillip Bay (14.0%) andApollo Bay (13.2%). The commoner causesof admittance were oiled plumage, starva­tion or broken limbs. The number ofpenguins received varied annually andseasonally. Annual admittance varied be­tween 28 (1986/87) and 176 (1989/90) andwas greatest in those years when oil spillincidents occurred. Juveniles were mostcommon in January and February (70.4%)and adults in March and April (70.5%).Adults (52.4%) were more successfully re­habilitated than juveniles (37.7%) butthere were no sexual differences. Over50% of penguins that survived were re­leased within three weeks and over 90%within eight weeks. The average stay for asuccessfully rehabilitated bird was 23.3days and the overall average stay 13.5days. Of the 295 Little Penguins released13.2% have been recovered over onemonth after release and of 63 known to beresident at the Penguin Parade 30.2% havebeen recovered over one month after re­lease.

IntroductionBreeding colonies of the Little Penguin

Eudyptula minor are found in southernAustralia, around the New Zealandmainland and its offshore islands includ­ing the Chatham Islands. In Australia, thebreeding range extends from CarnacIsland near Perth (W.A.) around thesouthern coast, the Tasmanian coast and

Wendy A. D'AmoreRosalind E. JessopPenguin ReserveCommittee ofManagementPOBox 97Cowes, Phillip Island, VictoriaAustralia 3922.

6

~ ..... ~.~ '0"

\) ;..

Phillip Island, Australia

north to Broughton Island near PortStephens (N. SW.) (Marchant and Higgins1990). The colony at Phillip Island is thesecond largest in Victoria with some 6000nests (Harris and Norman 1981).

Breeding on Phillip Island can begin asearly as May with the main egg layingperiod between August and November(Reilly and Cullen 1981).

Juvenile mortality is high (66.7%) inthe first twelve months with the majoritydying in the first six months (Dann andCullen 1990; Dann et al. 1992). Many juve­niles die of starvation which may beaccompanied by a high parasite load(Harrigan 1992). Adult mortality is highestin the pre-breeding and post-moultingperiods (March to October) (Dann et a1.1992). Banding recoveries of dead adultsand juveniles from Phillip Island aremostly west of the colony (95.3% and92.6% respectively) with adults more con­centrated in Port Phillip Bay, (64.8% ofadults compared to 4.3% of juveniles,Dann et al. 1992). Juvenile recoveries wereconcentrated on the coast between Lomeand Warrnambool with recoveries as faras the Gulf of St. Vincent in South Austra­lia (Dann et al. 1992).

The only published information on therehabilitation of sick and injured LittlePenguins reports on their treatment andcare (Twaites 1976). In this paper wepresent data collected at Phillip Islandbetween 1 July 1984 and 30 June 1992 onthe causes of injury and sickness in LittlePenguins, the success rate of rehabilitationfor different years and the seasonal varia­tion in the numbers washed ashore in adebilitated state.

ROSA LIND E. JESSOP

MethodsTreatment regime

The sick and injured birds weretreated according to the regime developedat the Penguin Reserve since 1984 Oessopet al. 1993).

Treatment facilitiesAll penguins were treated at a rehabili­

tation facility located within the PenguinReserve. In 1992 this facility was upgraded(Penguin and Koala RehabilitationComplex (PKRC» to include an air­conditioned penguin ward for criticalcare, a large fully enclosed outdoor penwith artificial burrows for long termpatients and separate treatment and foodpreparation areas. An oval saltwater chlo­rinated pool (5m long, 3m wide and 105mdeep) was also built in 1992 and this hasproved invaluable for exercising birds andtesting if their plumage is waterproof be­fore release.

ReleaseWhen weather conditions were suit­

able i.e. calm conditions likely for the nextthree days, rehabilitated penguins wereflipper-tagged with bands supplied by theAustralian Bird and Bat Banding Schemesand released into the water (in groups ifpossible) at Summerland Beach (PenguinParade). Their progress was observedthrough binoculars from a surroundingcliff-top until the birds were 500m off­shore. The area is dog-free and easilymonitored for returning birds if releasewere unsuccessful. The beach was fre­quently checked for returning birds on theday of release. Birds lUlsuitable for releasewere sent to the Royal Melbourne Zoo forinclusion in their breeding stock or wereeuthanized.

For this analysis birds whose first ad­mittance was to another wildlife shelterhave been excluded.

Penguin Conservation July 1995

AUSTRALIA

tored. Although all birds released from thePKRC were banded our analysis of sur­vival rate after rehabilitation was limitedto birds which are known to have origi­nated in the Penguin Parade nest~garea.

The regular and comprehensive monitor­ing of the Parade area (nest inspections,banding and weighing) means that thebest indication of recovery rates of reha­bilitated birds can be done using the datafor birds that originated in this section of

please turn to page 8

""-""-~EW ZEALAND

Tasmania ~ ""-U ""­/" ""-",,-

Chatham. Island ""- ""-

""-

----------------------------------------------

Survival rateThe survival rate of rehabilitated ani­

mals released into the wild is oftendifficult to obtain. The natal colony of anunbanded penguin washed ashore atPhil­lip Island is impossible to determine, andbirds found on land may come from partsof the colony that are not regularly moni-

ApolloBa~ \~Pori Phillip Bay

Pt. Nepean Venus Bay

O P~~ ~~t erson .t-stf (1t1'(155

~o

Penguin Conservation July 1995 7

Causes of Sickness and Injury in Little Penguins

continued from page 7

the colony. Birds from other areas of theIsland or from elsewhere would have asmall chance of being recovered. The Pen­guin Parade section of the colony containsaround 900 nests. Birds have only beenincluded if they have been found alive, ordead from an independent cause (not re­lated to that which brought them to thePKRC), at least one month after release.

Results and discussionThe Phillip Island Penguin Reserve

received 670 penguins for treatmentbetween 1 July 1984 and 30 June 1992. Themajority of these birds (60.4%) were foundon Phillip Island by Reserve staff and thepublic. Other common sources includedPort Phillip Bay (14.0%), Apollo Bay(13.2%), Point Nepean (3.0%), Venus Bay/Inverloch (3.0%), Torquay (2.0%) andCape Patterson (2.0%).

Annual variation in numbers ofpenguins treated

The number of penguins treatedvaried from year to year (Figure 1, page11). Increased numbers in 1985/86 and1989/90 were the result of large numbersof oiled penguins (Figure 2, page 12). In1985/86,61 oiled penguins were received,58 from one incident offshore from thePenguin Reserve. In 1989/90, 133 birds,mainly from an oil spill off Apollo Bay

(112), were treated. In 1990/91 and1991/92 higher numbers were the result ofmany penguins being found washedashore or starving on land. The majority ofthese birds were in their first year(1990/91 54.2%; 1991/9266.7%). Althoughbreeding success was above the long-termaverage of 0.84 chicks fledged per pair(Dann and Cullen 1990) in 1990/91 (Table1), weights of fledglings were low, espe­cially towards the end of the breedingseason (pers. obs.), resulting in increasednumbers of starving chicks. In 1991/92,breecting success was below the long-termaverage (Dann and Cullen 1990) (Table 1)and adults traveled long distances to findfood (Collins 1993) resulting in chicksbeing abandoned by their parents beforefledging, or fledging at low weights. Thesefactors probably contributed to the largernumbers of starved, beach-washedpenguins during these two seasons.("Beach-washed" penguins are thosewhich have been washed ashore and aretoo weak to flee when approached by ahuman being.)

Seasonal patterns of livebeach-washed penguins

Beach-washed penguins form asignificant component of the penguinstreated at the PKRC each year (Figure 2).The number of live beach-washed pen-

guins treated each month is shown in Fig­ure 3 (page 12). Most birds were receivedbetween January and April. In Januaryand February the majority (70.4%) werefirst year birds, but in March and April,adults (70.5%) were the main component.These results differ from those reportedfor dead, beach-washed, banded penguinsby Dann et al. 1992, who found that thedeaths of first-year birds recovered awayfrom Phillip Island peaked in April andadults in September, although a smallerpeak was recorded for adults in April/May. This perceived difference may bedue to the fledging behaviour of first yearbirds which leave their natal colony atPhillip Island and travel westward wherethey presumably remain for the first yearof life (Reilly and Cullen 1982). Juvenilesrecovered at Phillip Island may be fromcolonies further to the east or birds tooweak to undertake the journey to thesouth-west coast. Adults beach-washed inthe March-April period were apparentlysuffering from starvation associated withmoult. The majority of birds moult at theirnatal colony (Reilly and Cullen 1983) andproblems associated with the process maybe expected to manifest themselves in thisvicinity. Generally wildlife shelters awayfrom Phillip Island care for penguinsbeach-washed in their locality.

Table 1. Release details for all Little Penguins rehabilitated at the Penguin Reserve between 1 July 1984

and 30 June 1992; the number of penguins whose first admittance was to the PKRC is shown in brackets f ].

Year Total treated Total released % released Sent to Zoo Breeding success

1984/85 54 113] 28 [5] 51.9 [38.5] 0 0.35

1985/86 93 [90] 44 1431 47.3 [47.8] 0 0.66

1986/87 28 [241 7 [7] 25.0 [29.21 0 0.80

1987/88 41 [391 8 [8] 19.5 [20.51 0 0.49

1988/89 54 [52] 22 [22] 40.7 [42.3] 2 [2] 1.14

1989/90 176 [62] 96 [31] 54.6 [SO.OJ 4 [2] 1.45

1990/91 98 [81] 43 [311 43.9 [38.3] 3 [31 1.56

1991/92 126 fl041 47 [38] 37.3 [36.51 4 [2] 0.71

Total 670 [4651 295 [1851 44.0 [40.0] 13 [9)

8 Penguin Conservation July 1995

Table 2. Causes of injury or illness of Little Penguins rehabilitated at the

Penguin Reserve between 1 July 1984 and 30 June 1992.

Cause of Number % of totaladmittance treated treated

Oiled 234 349Beach washed 157 23.4Starvation on land 96 14.3Broken limbs and injuries 50 7.5

Biogenic toxin 39 5.8Fox and dog attack 25 3.7

Eye injuries 22 3.3

Heat stress 7 1.1

Car 6 0.9Other 27 4.0Unknown 7 1.1

Total 670 100.0

Causes of sickness and injuryThe causes of sickness and injury of

Little Penguins brought to the PKRC aresummarized in Table 2. The largest cat­egory was oiled penguins due mainly tothe spills mentioned above, althoughsome oiled penguins were receivedthroughout the year.

Beach-washed penguins includedfirst-year birds (36.9%) suffering fromstarvation in conjunction with parasitism,pre- and post- moult adults suffering fromstarvation (21.0%) and birds with undeter­mined conditions (42.0%). Beach-washedbirds with known injuries, e.g. eye inju­ries, are included in other categories(Table 2). Obendorf and McColl (1980) andHarrigan (1992) report that beach-washedbirds are generally in poor body conditionwhich may be accompanied by moderateto heavy internal and external parasiticburdens. In some cases mortality wasdirectly due to starvation or to the exacer­bation of the effects of existing parasiticburdens on starving and exhausted birds.In the latter case, deaths could be attrib­uted either directly due to parasitic lesions(e.g. acute hemorrhagic gastric ulcers)or indirectly to the effects of parasites (e.g.chronic gastric ulcers producing appetitedepression and thus exacerbating the lackof food).

The category "Starvation on land" in­cluded chicks abandoned by their parentsdue to food shortages or the onset of adultmoult at the end of the breeding season,and also included pre- and post-moultadults (Table 2).

Broken limbs and other injuries suchas nerve damage in legs were often theresult of plastic pollution, (e.g. fishingnets, fishing line, six-pack holders),man-made structures, (e.g. wire fences,Telecom pits-two-foot deep holes in theground where telephone lines are joined),and natural or exotic vegetation (Table 2).The number of penguins with this type ofinjury doubled between 1984/85 and1991/92, from 4-5 cases each year in theinterval 1985/86 to 1988/89 to 9-11cases between 1989/90 and 1991/92. Be­sides causing entanglement, plastic maybe mistakenly swallowed by penguins

Penguin Conservation July 1995

while catching fish, and studies at PhillipIsland have shown the incidence of inges­tion of synthetic material increasedelevenfold between 1980 and 1990 (Dann1990).

Thirty-nine penguins suffering symp­toms thought to be the result of ingestingbiogenic toxins (Norman et al. 1992) inPort Phillip Bay were treated in 1984/85(Table 2).

The major threats to penguins whenthey are ashore are dogs and the intro­duced red fox. Although the Reserve hasinvested extensive resources into the con­trol of these predators, many penguins arestill killed by them each year. Mortalityfrom this cause in recent years has rangedfrom 93 to 273. A few birds are found aliveafter attacks by dogs or foxes, but rarelyrehabilitate successfully. Birds often sufferparalysis resulting from nerve damage orswelling in the neck region, which is themost common bite site, and may recoverover a long period of time. Harrigan (1992)reports that Little Penguins killed byfoxes/dogs exhibited hemorrhage in thesubcutaneous tissue below the bite si teand often had tears in the neck musclesdespite there being little laceration of theoverlying skin.

The incidence of eye injuries increasedalarmingly during 1991/92 with 15 birdsfound. Only seven birds with eye injurieswere found during the period 1984-1990.Generally the cause of these injuries isunknown and the birds are beach-washed.Some injuries have resulted from the seedsof exotic grass species such as Bromus sp.being caught between the eye globe andthe eyelid. The injuries are often old andthe bird has already lost the sight of theeye. As they are unable to hunt efficientlythey are sent to the Melbourne Zoo oreuthanized.

Little Penguins cannot withstand highair temperatures due to a reduced capac­ity for evaporative cooling. They cannotpant like many other seabirds; instead,they hyperventilate. Hyperventilation isenergetically expensive, disrupts the acid­base status of the body and does notprevent their internal body temperaturefrom rising (Stahel and Gales 1987). LittlePenguins are most vulnerable to heatstress when periods of hot weathercoincide with incubation or moult (Staheland Gales 1987). All instances of heatstress reported here were during themoulting phase. When Little Penguins

please turn to page 10

9

Causes of Sickness and Injury in Little Penguins

continued from page 9

Table 3. Numbers of rehabilitated Little Penguins, released and recovered at

the Penguin Reserve between 1 July 1982 and 30 June 1992.

Survival rateA total of 295 penguins (adults and

juveniles) have been released followingtreatment and 13.2% (Table 3) were suc­cessfully located again following release(30 alive and 9 dead). Of the releasedbirds, 63 were adult penguins resident inthe Parade and 19 (30.2%) have been suc­cessfully recovered (all alive). There wasno significant difference in the recoveryrate of males and females (X2, p>0.(5).None of the 9 chicks from the Parade that

within this period. This is especially truefor juveniles: e.g. in 1991/92, 20 juvenilesdied within 24 hours of admittance.Adults (51.3%) are more successfully reha­bilitated than chicks (30.4%) (X2, p<O.O 1).It appears that many factors effect the per­centage of penguins that are successfullytreated. Among these are the annualbreeding success, the initial weight andage of the penguin and the complaint. Forexample, oiled penguins have a relativelyhigh rate of rehabilitation (approximately59%). In 1985/86 when a large number ofthe penguins treated were oiled, there isan elevated rate of release (Table 1 ).

Over 50% of penguins that survive arereleased within the first three weeks andover 90% within eight weeks. The averagestay for a successfully rehabilitated bird is24.0 days and the overall average is 13.7days. Nearly 79% of birds that died did soduring the first week of rehabilitation andthe average stay for birds which were notreleased was 6.6 days.

Number

released (1)

AcknowledgmentsWe wish to thank all those who as­

sisted with the rehabilitation of LittlePenguins at Phillip Island includingMargaret Healy and veterinarians:Karl Harrigan, Jenny Hibble and MarkMackie. We are grateful to the AustralianBird and Bat Banding Schemes for thesupply of bands and administration ofrecoveries from the public and we thankthe National Parks and Wildlife Divisionof the Department of Conservation andNatural Resources for permits to bandbirds in Victoria and to maintain a wildlifeshelter. We would also like to thank MikeCullen for statistical advice and PeterDann and Margaret Healy for readingearly drafts of this manuscript.

ReferencesDann, P. 1990. Plastic pollution and

penguins. Australian Ranger Bulletin 5:49­50.

Dann, P., and Cullen, J.M. 1990. Sur­vival, patterns of reproduction, andlifetime reproductive output in Little BluePenguins (Eudyptula minor) on Phillip Is­land, Victoria, Australia. In: PenguinBiology (Eds. L.S. Davis and J.T. Darby.)pp. 63-84. (Academic Press: San Diego.)

Dann, P., Cullen, J.M., Thoday, R., andJessop, R. 1992. Movements and patternsof mortality at sea of Little PengUinsEudyptula minor from Phillip Island,Victoria. Emu 91 :278-86.

Collins, M. 1993. Radio-tracking at seaof penguins which breed on the northernside of Phillip Island. In: Phillip Island Pen­

guin Reserve Committee of Management,Annual Report 1991-92. (Anonymous.) p. 6.(Phillip Island Penguin Reserve: Ventnor,Victoria, Australia.)

Harrigan, K.E. 1992. Causes of mortal­ity of Little Penguins Eudyptula minor inVictoria. Emu 91:273-77.

were rehabilitated and released have beenrecovered. Of the 63 adult penguins re­leased, 39 (61.9%) were rehabilitated afteroil spills and 16 or 41 % of these have beenrecovered. Of the remaining 24 birds onlythree or 12.5% have been recovered.

30.2

13.2

% recovered

(2 as % ofl)

39

19

Number

recovered (2)

63

295

Number of rehabilitated adultsfrom the Parade, released and

recovered in the Parade

Total number ofrehabilitated penguins

Percentage of penguins releasedFour hundred and sixty-two of the 670

penguins trea ted at Phillip Island had thePKRC as their first animal shelter of ad­mittance. Of these 428 have adequaterecords for analysis. The percentage ofpenguins released each year is shown inTable 1. The total number of penguins in­cluded those that died within 24 hours,those that were euthanized, and those sentto the Melbourne Zoo. The first 24 hours isthe most critical period for sick and in­jured birds and 25.8% of the deaths thatoccurred during this study, occurred

undertake moult in February to May, theymay double their body weigh t, by increas­ing their fat store, so they can fast forapproximately 17 days while they replaceall their feathers (Reilly and Cullen 1983).Trapped in their burrows, away from thecooling effects of the ocean, with theirmetabolic rate already increased due tothe moulting process, they are at theirmost vulnerable to heat stress at this time.Heat-stressed birds were often foundwalking out in the open during daylighthours. They rarely recovered. .

Most penguins hit by cars die, and thefew that make it to the PKRC have a slimchance of survival.

Other conditions included a prolapsedcloaca (occurring during egg laying),being kidnapped by humans (stolen fromthe colony and released elsewhere e.g. citystreets), tumors, brain damage, deformi­ties, paralysis and being trapped in drainsor ditches.

10 Penguin Conservation July 1995

Harris, M.P., and Norman, F.I. 1981.Distribution and status of coastal coloniesof seabirds in Victoria. Memoirs ofMuseumof Victoria 42:89-105.

Jessop, R., D'Amore, W., and Healy,M. 1993. Regimefor treating sick and injuredpenguins. (Phillip Island Penguin ReserveCommittee of Management: Ventnor.)

Marchant, S., and Higgins, P.J. 1990.Eudyptula minor. In: Handbook ofAustralian,New Zealand and Antarctic Birds. Vol. 1, pp.246-59 (Oxford University Press:Melbourne.)

Norman, F.I., Du Guesclin. P., andDann, P. 1992. The 1986 'wreck' of Little

Penguins Eudyptula minor in westernVictoria. Emu 91:369-76.

Obendorf, 0.1., and McColl, K. 1980.Mortality in Little Penguins (Eudyptula mi­nor) along the coast of Victoria, Australia.Journal of Wildlife Diseases 16:251-59.

Reilly, PN., and Cullen,].M. 1981. TheLittle Penguin Eudyptula minor in Victoria,II: Breeding. Emu 81:1-19.

Reilly,P.N., and Cullen,].M. 1982. TheLittle Penguin Eudyptula minor in Victoria,ill: Dispersal of chicks and survival afterbreeding. Emu 82:137-41.

Reilly, P.N., and Cullen, J.M. 1983. TheLittle Penguin Eudyptula minor in Victoria,IV: Moult. Emu 83:94-8.

Stahel, c., and Gales, R. 1987. LittlePenguin. Fairy Penguins in Australia.(New South Wales University Press:KenSington.)

Twaites, P. 1976. The treatment andcare of sick Fairy Penguins. Thylacinus1: 32-5. ..

180

160

~ Died

DToZoo

• Released

o

40

20

en 120c:.::;0>

~ 100c-oiii 80.0E~ 60

140

1984/85 1985/86 1986-87 1987-88 1988-89 1989-90

Year

1990-91 1991 -92

Figure 1. Number of Little Penguins treated at the Penguin Reserve 1 July 1984 to 30 June 1992.

Figures 2 and 3appear on page 12

Penguin Conservation July 1995 11

Causes of Sickness and Injury in Little Penguins

continued from page 11

140

120

100

• Oiled

~ Poisoned

II Beachwashed

13 Starved on land

o Other

Vlc:·Sg> 80Q)0..

'005 60..cE:::lZ

40

20

o1984/85 1985/86 1986/87 1987/88 1988/89 1989/90 1990/91

Year

1991/92

Figure 2. Causes of sickness and injury to Little Penguins treated at the Penguin Reserve 1 July 1984 to 30 June 1992.

• Adults

11II Juveniles

o Unknown

DNaSAJ J

Month

MAMFJ

o

25

5

Vl 20c:·SClc:Q)

2- 15o~

Q)..cE~ 10

30

Figure 3. Seasonal variation in the number of beachwashed Little Penguins treated at the Penguin Reserve1 July 1984 to 30 June 1992.

12 Penguin Conservation July 1995

Sharks in the GalapagosWILLIAM C. BURNS

13

harvest, and facing pressure from variousinternational organizations and groups,promulgated a memo to his ministers. Itcalled for stricter measures to protect theGalapagos, including a prohibition on allshark fishing within the Reserve and aproposal to expand the Reserve to fortymiles from the coastline.

In response to this measure, maskedfishermen seized control of the CharlesDarwin Research Station and GalapagosNational Park headquarters, demandingtha t the sea cucumber industry be reopened.In the face of this pressure, and disturbingreports tha t land tortoises were beingslaughtered as part of the protests, the gov­ernment subsequently agreed to reconsiderreopening the sea cucumber fishery. If thegovernment capitulates in this context, itmay be an ominous signal for sharkconservation measures also. Concernedgroups and individuals are encouraged towrite to the President of Ecuador, urginghim to implement a total ban on shark fish­ing in Galapagos waters, as well as provideadditional law enforcement personnel to

ensure better enforcement of nationalconservation laws. Letters should be

directed to President Sixto Duran­Ballen, Garcia Moreno 1043, Quito,Ecuador. Also, contact your travel

agent and Voyagers International, amajor travel agency for Galapagos

eco-tourism, and encourage them tospeak up on behalf of tourists who wish to

protect the ecosystem of the Galapagos.For additional information on the plight

of sharks in the Galapagos, and other partsof the world, contact the author.

The Center has recently launched theShark Education Project (SEP) to educate thepublic and policymakers about one of themost maligned and misunderstood

creatures on earth. Membershipsin SEP are available for $15.00

annually. "

Sea cucumber

Galapagos Islands

cut off, leaving the bleeding fish to spiral tothe bottom of the ocean. These barbaricpractices have been committed both byEcuadorean fishermen and Japanese, Ko­rean and Taiwanese fishing vessels that arelicensed to legally fish for tuna outside themarine reserve wne. Many sharks are killedas bycatch in gillnets and longlines used totarget other fish.

The Ecuadorean government exacer­bated the crisis in June of 1994 when itannounced that it would permit fishers tolegally fish for sharks, and several other spe­cies, including sea cucumbers and lobsters,in Reserve waters beyond three miles fromshore.

The result ofthe "experi­mental" seacucumberfishery is achilling por­tent to theescalatingthreat this policy could pose for sharks.While a quota of555,000 was set by authori­ties for a three month period, an estimated6-10 million sea cucumbers were takenduring this period. Given the fact thatvirtually every commercial shark fisheryin the world has proven whollyunsustainable, the already fragile sharkpopulations of the Galapagos could likelyface collapse within a few years ifcommercial fishingoperations werepermitted. OnSeptember 27,1994, PresidentSixto Duran-Ballen,shaken by the magni­tude of the sea cucumber

[This article does not deal directly withpenguins, but with threats to the marineecosystem in which resides the GalapagosPenguin, with an estimated population ofonly1,()()()-3,OOO pairs. In addition to the dramaticevents described here-which took place inDecember 1994-January 1995-there are con­cerns (The Oregonian, March 9, 1995) that seacucmber fishermen are cutting the mangroveforest for fuel to boil their catch, and that illegalfishing camps may be asource ofintroduced miceand rats which could threaten the islands'indigenous animals and plants. -Editor]

The Galapagos Islands have beentermed the "Natural Laboratory of Evolu­tion," supporting a tremendous array ofspecies, many of which are not found any­where else in the world. Some of the mostimportant inhabitants of the Galapagosecosystem are the twenty-seven species ofsharks indigenous to the area, including sev­eral rare species of hammerheads, great,smooth and scalloped. Unfortunately, thefuture viability of chondrichthyan species inthis area is open to serious question becauseof massive overexploitation in recent years.This article will outline the threats faced bysharks in the Galapagos, and what can bedone to avert a catastrophe in this context. In1959, the Ecuadorean government createdthe Galapagos National Park, providingprotection for terrestrial species on theislands. In 1971, the islands were declared aWorld Heritage Site, and a Man in the Bio­sphere Reserve in 1982. In 1986, Ecuadorextended protection to marine species bycreating the Galapagos Marine ResourcesReserve, establishing a 15 mile protectionwne from the islands' shore lines. DespiteReserve designation, tens of thousands ofsharks have been illegally taken in Galapa­gos waters in the past decade, primarily tosupply the Asian shark fin soup market. Inmany cases, the fins of the sharks have been

Penguin Conservation July 1995

William C. Burns, DirectorPacific Center For International Studies33 University Square, Ste. 184Madison, Wisconsin 53715-1012 USAphone: (608) 257-6309,fax: (608) 257-0417e-mail: pcis@binc.netalternate e-mail: ecoguy2336@aol.com.

Population Status of Penguin Species in the Falkland Islands

MICHAEL BINGHAM

IntroductionAims and Objectives of the FISMP

The Falkland Islands hold a rich varietyof wildlife, important both locally and inter­nationally, much ofwhich is either unique orfound in globally significant concentrations.During recent years a number of potentialnew threats have emerged, such as fisheries,tourism, and possible oil exploration, mostlyconcentrated on coastal habitats. TheFalkland IslandS Seabird MonitoringProgramme (FISMP) was established byFalklands Conservation (formerly FalklandIslands Foundation). The aim was to docu­ment changes in seabird populations and,where possible, identify the causes so thatearly warning could be given of any harm­ful effects. We have now obtained sufficientdata to draw preliminary conclusions for thefour main species of penguin found breed­ing within the Falklands archipelago.

This article presents those conclusions,along with a sununary of the methods usedand the population and reproductive datacollected.

MethodologyOn the basis of an initial survey during

1986/87 and 1987/88 the FISMP hasconcentrated on Black-browed Albatross(Diomedea melanophris), and the 4 mainbreeding penguins-Gentoo (Pygoscelispapua), Magellanic (Spheniscus mage1lanicus),Rockhopper (Eudyptes chrysocome), and King(Aptenodytespatagonicus). During 1993/94anemphasis has been placed on expanding an­nual study-eolony counts into large-scalepopulation counts, so as to allow statisticallysignificant comparisons to be made withprevious population counts. This has en­abled Falklands Conservation to assesswhich species are presently increasing, andwhich are declining, and in such cases tolook for patterns and causal factors.

MicJuzeI BinghamConservation OfficerFalklands ConservationStanleyFalkland Islands

14

Falkland Islands

Methodology For All SpeciesExcept Magellanic Penguin

All colony and popula tion counts aregiven as numbers of breeding pairs. Theseare determined by direct counts (using taJIy­counters) of the numbers of incubating birdsat the start of the breeding season (Le. priorto reduction of breeding numbers due to re­productive failure). All counts are madethree times, the mean being taken as the re­sult and the spread giving an indication ofthe margin of error (usually well below±5%).

Chicks are counted in the same way(again three times) just prior to fledging.ProductiVity is given as the number ofchicks produced per breeding pair in thecolony, and is expressed as a percen tage.Productivity can of course exceed 100% onoccasions, for species laying more thanone egg.

Diet samples are taken in late after­noon from adults returning from theocean to feed chicks. A small tube ispassed down the throat into the stomach,and sea-water gently pumped into thestomach until full. The penguin is thenquickly inverted and the tube removed~asthe stomach contents and water are col­lected in a bucket. This procedure isrepeated 3 or 4 times until the water isclean and the stomach empty. The pen­guin is then marked with a dye-stick toprevent recapture, and released. Thewhole procedure is quick and safe, al­though it clearly causes a certain degree ofstress and discomfort.

The samples are drained and placed informal saline immediately after collection.At a later date they are sorted in detail togive total sample weight, and proportionby weight of the various prey species mak-

ing up the sample. Fish otoliths, squidbeaks, etc. are used to determine speciesand size of prey.

MethodologyFor Magellanic Penguin Only

Due to the fact tha t the MagellanicPenguin lives in burrows in the Falklands,direct counting methods used for all otherspecies are not possible. Instead of attempt­ing to count entire colonies, permanentstudy-plots are monitored annually todetermine popula tion trends (as opposed toactual numbers). These plots are locatedwithin main colonies and are believed to berepresentative.

After the completion of egg-laying, eachburrow in the study-plot is examined todetermine the number of breeding pairs.Each burrow is then re-examined just priorto fledging, and the number of chickssurviving recorded. Productivity is givenas the average number of chicks rearedper breeding pair for the study-plot, and isgiven as a percentage.

Five fixed transects, each with fiveequally spaced quadra ts spanning thecolony, were used to supplement the study­plot data. The number of occupied burrows,chicks surviving to fledge, and productivitywere all determined in an identical way tothe study-plots.

Diet-sampling of Magellanic Penguinswas exactly as described for all other species.

Data CollectedData collection during 1993/94 has em­

ployed the same methods as previous years,but the data analysis has been revised inorder to standardize the results for each spe­cies and to allow easier iden tifica tion oftrends. For each species the main data re­quired is as follows:

1) Breeding pairs for each colony (orpopulation) and comparison with previousseasons to determine trends.

2) Productivity: The number of chicksfledging per colony (or popilla tion) dividedby the number of breeding pairs (chicks/

Penguin Conservation July 1995

nest). These can be compared with previousseasons in order to identify good or bad sea­sons and colonies, and possible causes.

3) Diet sampling of species believed tobe in decline, in order to investigate possibleconnections between their decline and theestablishment of squid and finfish fisheriesaround the Falklands. The three speciesidentified as being in decline are Gentoo,Magellanic and Rockhopper Penguins.Black-browed Albatross and King Penguinsare increasing.

Results

50000

~"iii 40000a.Clc:'U 30000(])

~..c0 20000

Ii>..cE 10000:::Jc:(ij0 0I-

1932/33

r950/51 1993194

•~ ~ ~ Ie t: ~ ~

~ g 0 8I"-

~ ~ ~ ~ ~ ~ ~

Year

Figure 1. Rockhopper Penguin population for Westpoint IslandKing Penguin(Aptenodytes patagonicus)

The Falkland Islands' population ofKing Penguin is largely located at VolunteerPoint on East Falkland, although very smallnumbers of birds can be found breeding inGentoo colonies at a few other locations. Thetotal population is presently increasing quitesteadily, probably through continuing im­migration from the large and rapidlyincreasing population at South Georgia. Itcannot therefore be considered threatened,despite being small (only 1% of the worldpopulation) (Table 1).

The irregular breeding cycle and nid­ifugous nature of the King Penguincomplicate measurements of productivity,hence data is presented merely as numbersofad ults and chicks. Since the population ison the increase, and of local rather than in­terna tional importance, the level ofdisturbance involved with diet-samplingsuch a small population does not seem jus­tified at present.

Table 1. King Penguin population

counts for East Falkland

Adults Chicks

1980/81 85 38

[KeenleysideI

1993/94 382 244

[FlSMPl

Penguin Conservation July 1995

Rockhopper Penguin(Eudyptes chrysocome)

An extremely numerous bird within theFalklands, the Rockhopper breeds in colo­nies on rocky cliffs at some 35 sites, mostlyin the west of the archipelago, and often inassociation with Black-browed Albatross.The Falklands population is the largest con­centration ofRockhoppers in the world, butis declining, and has probably been doing sofor at least 60 years (Figure 1).

This decline became particularly notice­able during the catastrophic season of1985/86, when mass starvation of adultbirds was reported from many colonies. Theworst affected colonies in the north and westlost over half their adults as a result. Thepresent low popula tion ofRockhoppers hasbeen attributed to this event, but recordsshow that dramatic declines had alreadyoccurred prior to 1985/86. The populationon Sea Lion Island had dropped from150,000 pairs in 1932/ 33 to just 1,000 pairsby 1981/82, and the population of Kidneyisland which numbered over 12,000 pairs in1914/15 had declined to just 3,000 pairs by1960/ 61. This suggests amuch more seriousproblem which may still be persisting today.Comparable declines have also been re­ported for the same species at severalsub-antarctic islands in the New Zealandarea. The causes are not understood but mayreflect long term changes in sub-antarcticmarine systems.

Research, particularly by Ian Keymer,into the 1985/86 event showed that theadults starved to death during their annualmoult. This was presumably due to aninability to find sufficient food to build upbody-fat reserves prior to moulting, and wasan unusually extreme indication of a severefood shortage. Another indicator of foodshortage is low chick survival, and during1985/86 the worst affected coloniesreared virtually no chicks. Low chick sur­vival was also observed throughout theperiod from 1986/87 to 1992/ 93, and onlyduring 1993/94 did study sites showimproved chick rearing success, averaging60-85% productivity (chicks per pair).The period since 1986/87 saw many fewerimmature birds returning to moult thanwould normally have been expected in ahealthy population.

A complete population count ofWestpoint Island was undertaken during1993/94 so as to allow comparison with pre­vious surveys conducted during 1932/33and 1950/51. The results indicate a persis­tent decline throughout this period, andsuggest that n umbers were dropping beforethe population crash of the mid 1980's. Rock­hoppers were not previously amongst themain species covered by the F1SMP so thatdata on colony counts and productivity israther limited. However, it was decidedfrom 1993/94 to include them in the FISMP.

please turn to page 16

15

Population Status of Penguin Species in the Falkland Islandscontinued from page 15

Figure 2. Magellanic Penguin population trends, as a percentage of the 1990/91population size, based upon counts in seven study plots

Penguin Conservation July 1995

100

90

~ 80III cE .2~]! 70 1-------t':::r:':'::::::r:':':::::\1-,--------

iii 6. 60 :I-- ---I~

U 50 :1------11=.~ ~ :.,.....,l-----{ f-----i 1-------1:....,:·,..,: ....::,..,1,..,:...,:....::..,:..,:.:.i..,:!....,;i,..,::....,:="[ £ - :::::tr ...,.".,., ~

~ 15 20 - ::tt:::: ..::!:..,..:.:..:::..,:..:.:....:..::..:!:::..:.:::..;.:..~:.:.:::..:.:::ll---~--i: :::::::::::::f---

10 - .:.,:~.,:.~.,..:,..i.,..:,..:~:f.:~,.:~.,:.::..::.: . I------i t------f.:.'...·.·.·.ii.i...:./f---. r.·~~.·~:.;r.~f.~~.~~.~o .L..-_....IOO"'"""L- ----""::::""':::;:::;: ----""=I.-- ---i;::""'::;::""':;:;::'-i..-__

Measurements of productivity indicatethat 1993/94 was a very successful seasonfor chick-rearing, but it remains to be s~nhow this affects the overall decline. (Theresults for Westpoint illustrate the short­comings of such a small study-plot, havingnow declined to just 16 occupied burrows.The low productivity indicated by thisstudy-plot for 1993/94 was in complete dis­agreement with the observations madegenerally around Westpoint, where mostcolonies had large numbers of chicks).

Living as they do in burrows, the chicksare well protected against both predationand the weather. Occasional flooding ofburrows does occur, but did not take placeduring the study. The most likely explana­tion of the low chick survival rate inprevious years is that adults were unable tofind sufficient food during the crucial chick­rearing stage.

The declining population trend between1990 and 1994 is obviously of concern, andFalklands Conservation intends to expand,but simplify, its monitoring programme toallow entire colonies to be monitored, ratherthan only sampling areas within a colony.The study-plots will continue to be moni­tored in the usual way alongside the newcolony counts initially, so as to evaluate the

new methods and to integrate the results forfuture compatibility.

Diet sampling at Volunteer Point(Table 8) indicate considerable interannualvariation but suggest for recent years areduction in the importance of cephalopodand an increase in the contribution of fish(mainly immature Blue Whiting). Althoughthere is considerable intersite variation inthis species, sampling in 1993/94 at BullPoint gave results of 99% Blue Whiting and1% squid.

1993/941992/93

Gentoo Penguin(Pygosce1is papua)

The Centoo is a fairly numerous birdwith small colonies scattered throughout theFalkland Islands. TheseCentoo colonies areof international importance, with approxi­mately one third of the world populationbreeding within the archipelago.

To complement the annual monitoringof individual colonies (and because SOmecolonies move and fragment betweenyears), Falklands Conservation undertook acomplete population count for East Falk­land, so as to make comparisons withsimilar surveys undertaken in 1987/88 and1932/33. The resul ts suggest that the popu­la tion size may have changed little between1932/33 and 1987/88 but suggest a possible

1991/921990/91

Magellanic Penguin(Spheniscus magellanicus)

The Magellanic Penguin is a very nu­merous bird in the Falklands and breeds ina wide range ofhabitats, from tussac grass tocrevices in sea cliffs. Although the Falklands'population is of international importance,accurate monitoring of its population statushas been complicated by its widespreadlow-density distribution, and its habit ofnesting in burrows. As a result few accuratedata on population size exist for the Falk­lands.

Falklands Conservation has previouslyrelied on monitoring seven study-plots atthree widely distributed locations since1990. These results all indicate a steady de­cline in Magellanic Penguins over this four­year period (Figure 2 and Tables 2 and 3),with the 1994 population being only twothirds of that found in 1990/ 91. This repre­sents a decline of around 10% per yearwhich would have catastrophic conse­quences if it continues. This decline could belargely a result of the current failure ofadults to rear sufficient young. During the1990/91, 1991/92 and 1992/ 93 seasons,colonies were producing less than half achick per pair (42% productivity) comparedto 1993/94 when one chick per pair wasreared (100% productivity).

16

They will now be monitored each year at anumber of sites for data collection on breed­ing pairs, productivity and diet. The data for1993/94, with 60% and 85% productivity atWest Point and Fanning Head sites, respec­tively, suggest that this has been their mostsuccessful season for several years, with re­gard to both productivity and number ofnon-breeders returning to moult

It is possible that a combination of alengthy period of low productivity and re­duced juvenile survival, coupled withoccasional years of high adult mortality,could account for the major population de­cline. Reduced food availability is the mostplausible explanation for these events.Whilst the cause of the decline remains un­certain, there would appear to be noevidence to link the decline with any land­based human activity in the Falklands.

Table 2. Magelianic Penguin burrow occupancy and productivity

Study plot Year Number of %of(A) Breeding

location occupied breeding success Number of

burrows of (B) chicks

= (A) = (B) =(q =(AxBxq Productivity

Bull Point 1990/91 51 100 % 50 % 25 50 %

1991/92 35 100 57 20 57

1992/93 24 86 43 9 37

1993/94 30 100 64 19 64

Volunteer 1990/91 146 98 56 80 55

Point 1991/92 127 100 39 50 39

1992/93 119 51 44 27 22

1993/94 100 98 126 123 123

Westpoint 1990/91 32 95 5 2 5

Island 1991/92 29 83 93 22 77

1992/93 19 100 36 7 36

1993/94 16 40 50 3 20

Gypsy 1962/63 20

Cove 1993/94 69

Table 3. Magellanic Penguin burrow occupancy and productivity transects

at Volunteer Point

Fixed transect number Total ProductiVity (%)----------Year 1 2 3 4 5 occupied (Chick/nest)

Number of occupied burrows burrows

1989/90 19 35 26 23 25 128 46 %

1993/94 11 6 6 9 8 40 129

Table 4. Gentoo Penguin population count for East Falkland

decline (totalling 16%) since then (Table 4).A more detailed analysis of those colonieswhose populations changed by more than20% between 1987/88 and 1993/94 (Table5), shows that northern colonies are increas­ing and the southern ones decreasing (by42% since 1987/88). Although a full censusof West Falkland is yet to be conducted,counts from a n umber of West Falkland andisland colonies indicate that a decline isoccurring in the west also.

Analysis of productivity shows 1993/94to have been a more successful year for chickrearing for Gentoo than the three previousseasons since 1990/91 (Table 6). Diet analy­sis shows adults returning to feed chicksbringing back larger quantities of food dur­ing 1993/94 than previous seasons (Table 7).Whereas the diet at Bull Point over five yearsof sampling contains very little squid «7%)and suggests substantial reliance on lobster

please turn to page 18

Penguin Conservation July 1995

Total number of

breeding pairs

1932/33(Bennett, unpub.)

18,000

1987/88

FISMP

18,000

1993/94

FISMP

15,000

17

Population Status of Penguin Species in the Falkland Islandscontinuedfrom page 17

Table 6. Gentoo Penguin colony counts and productivity, 1993/94,

and comparison of productivity with earlier years

Table 5. Comparison of Gentoo Penguin colonies

in the North and South of East Falkland

Number of breeding pairs

1987/88 1993/94

krill, the diet in northern (Volunteer) andwestern (New Island, Beaver Island) siteshas contained more squid and much lesslobster krill.

There are no indications that the differ­ent population trends at northern andsouthern Gentoo colonies, and any overalldecrease in numbers that may accompanythese trends, relate to differences in distur­bance or landbased human activity such asegging and tourism. Local differences inweather or in predator impact also seemunlikely. Regional differences associatedwith the marine ecosystem seem potentiallymore plausible. There is an obvious need toobtain more data on differences in diet andbreeding productivity between northernand southern colonies and to relate this toinformation on the local oceanographicconditions and to the nature and magnitudeof recent and current fishing activity. Thescarcity of cephalopods in the diet of the BullPoint birds compared to northern and west­ern colonies is of particular interest andpotential concern.

Conclusions

Location

Yolunteer

Limpet Creek W

Limpet Creek EColorado Bay

North Pond

Black Point

Strike Off Point

Bull Point

The Sandhi1ls

Bluff Bead

Moffit Harbour

CraigleaPort Edgar

Location

450

100

20

30

100

200

200

4.250

450

700

96

8002,500

Breeding pairs

93]

53075

42

400

300130

2.919

210

200

70

oU52

Changes of

over 20%

up

up

upupup

updown

down

down

down

down

down

down

Chicks

North/South

N

N

NN

NNNSSssss

Productivity(Chicks/nest)

Bertha's Beach 312 398 127

Kidney Cove 1 622 1 772 109

Rookery Sands 180 75 4]

1993/94 SeasonAll 4 species of penguin covered by the

FISMP seem to have had a successful yearfor chick rearing during 1993/94, with pro­ductivity rates for all species being higherthan for previous seasons. This wouldseem to be as a result of better feedingconditions.

Bull Point 2 919 2 391

VollUlteer 931 540Cow Bay 91 78

Fanning Harbour 170 194

Paloma Beach 470 248

82 %5885

114

Beaver Island 795 324 41

Fox Point 425 408 96

Port Edgar 1152 1181 102

Seal Bay 765 %1 126

70

51

82

Average annual productivity

1991/92

1990/91

1992/93

1993/94

....P-"'OLLr......t NULUoc.urtUJh'-- ""63.u7 ----"'406'"""'- --'6::r..4 _

Great Island 250 70 28

Overall population trendsIt is a matter of serious concern tha t,

apart from King Penguins, populations ofthe species of penguin breeding in the Falk­lands are all declining. The nature of thedecline is different for each species: theRockhopper has undergone a very severedecline over a period of at least 50 years,whilst the decline of the Gentoo is recent.Insufficient historic information exists forthe.Magellanic Penguin to determine theduration of its decline. The underlyingcauses of these population declines maywell be linked, with difference in trends be­

ing the result of variations in life cycle,

18 Penguin Conservation July 1995

Table 8. Magellanic Penguin diet at Volunteer Point

Year Prey type (proportion ('Yo) by weight) Average weightLobster Krill Cephalopod Fish collected for chicks (g)

1989/90 33 64 3

1990/91 0 91 9 573

1991/92 0 93 7

1992/93 36 26 37 3821993/94 0 43 57 "" 403

Average(%) 16 67 17 459

710

453

500

557

364

Average weight (g)collected for chicks

34

Falklands Conservation~ may be contacted at:.~~... 1 Princes Ave., Finchley,

London N3 2DA UK; tellfax 081 3430831.Its activities include the support of research onFalklands wildlife and recently the purchase oftwo groups of small islands to keep as naturereserves. Publications include its newsletter,TheWarrah.

4

""Fish almost entirely immature Blue Whiting

48 7 45

86 7 7

77 3 20

62

56 3 41

65 4 31

Prey type (proportion (%) by weight)Lobster Krill Cephalopod Fish

Average ('Yo)

Year

1991/92

1993/94

1990/91

1992/93

1989/90

declines have transcended geographic andtaxonomical boundaries, suggests that all isnot well.

AcknowledgmentsFunding support for the FISMP has

been provided by the Falkland IslandsGovernment.

Tim Stenning and Jeremy Smith assistedwith field and laboratory work.

Carol Miller handled the administration.Logistic assistance has been provided

by the Fisheries Dept.Thanks to all landowners who gave

access to study sites, and to all the volunteercounters who monitored their adopted

colonies on our behalf...

habita t and adaptability between the spe- ....:T:...:a~b..:.:le::...:7:....:.....:G::.:e~n:..:;too~P~e=n::.lg:>..:wn:::·::...:::d:.::ie::.:t:...:a:..:;t..=B..=ul::;I....:P....:0:..:oin:..:;t=--- _cies.

There is no evidence that disease,predation or terrestrial climatic factors areresponsible for the observed decline or lowchick productivity, and such factors wouldnot explain the north/ south split in Gentoopopulation trends, or the fact that successfulbreeding seasons coincide amongst threespecies with such differing nesting habitsand locations.

Magellanic Penguins nest in burrows,whilst Rockhoppers and Gentoos nest incolonies above ground, on sea cliffs and lowlying coasts respectively They all exploitsimilar oceanic food (krill, cephalopods andfish). Whilst there are differences in pre­ferred diet between the three species, theyare all able to switch between prey species asabundance dictates.

The most critical period for finding foodis during chick rearing. If food is in shortsupply, chick survival will suffer. Monitor­ing of colonies by Falklands Conservationhas shown that chick production has beenpoor for all three species, with the exceptionof 1993/94 when all species had a successfulseason (Rockhoppers 60-85%; Magellanic64-129%; Gentoo 41-126%; with one chickper pair equalling 100%). This improvementin chick production was almost certainlydue to greater food availability, and this issupported by increased food catches peradult being recorded during chick rearing in1993-94.

The information we have at present isbroadly consisten t with a general red uctionin the average levels of food available topenguins, with the most pelagic species(Rockhoppers) apparently affected moreseriously and over a longer period thaninshore feeding species (Gentoo). It isunlikely that it will be possible to reconstructpast events but the Seabird MonitoringProgramme will follow future changesvery closely and attempt to match these tochanges in the amount and type of foodavailable to penguins.

This work re-emphasizes tha t penguinscan be a useful indica tor of the heal th of oursouthern oceans; very clearly the magni tudeof their current declines, and the way these

Penguin Conservation July 1995 19

Penguin Conservation

ISSN # 1045-0076Indexed in: Wildlife Review and Zoological Record

[Previous title was SPN: Spheniscus Penguin Newsletter. Volume numbering continued from previous title.]Printed on recycled paper.

Penguin Conservation is published three times per year, with financial support from the Metro Washington ParkZoo, the Portland Chapter of the American Association of Zoo Keepers, and from its readers. Subscription is free, tothose with a serious interest in penguin conservation and study. Contributions toward printing costs are welcome:please make checks payable to "Conservation Publications," and send to the Editor at the address below. Suggestedamount is US$15; please remit in US$ or with a bank draft upon a bank that has a US affiliate.

The draWing which serves as our cover logo is reproduced by kind permission of the artist, Ann Munson.Articles submitted for publication should be typed. For articles which include graphs (such as line or bar graphs)

please include a separate sheet giving the data used to generate the graph. Authors who work on a Macintosh computercan help our editorial process by sending their work on disk as well as on paper.

Articles for the next issue must be received by Aug. 20, 1995.

Please address all correspondence to:

Cynthia Cheney, EditorPenguin ConservationMetro Washington Park Zoo4001 SW Canyon Rd.Portland, Oregon 97221 USA

Telephone: 503/226-1561FAX: 503/226-6836e-mail: 71612.1336@compuserve.com [within the Compuserve system, use: 71612,1336]