Pringle 1986 California Spiny Lobster Recruitment
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ifornia Spiny Lobster (Panulirus interruptus tention and Recruitment: A Review and Syj. D. PringleDepartment of Fisheries and Oceans, Fisheries Research Srdnch, Scotra-Fundy Region, Invertebrates and Marine Pjants Division, Halifax Fisheries Research Laboratory, 1 . .Box 550, Halifax, N.S. B3/ LS7 00
1. 0. '1 986. California spiny lobster (Panulirus interruptus) larval retention and recruitment: a review andsynthesis. Can. j. Fish. Aquat. Sci. 43: 2142-2152.
The late Dr. ha. W. johnson studied Panulirus interruptus phyilosorne larval natural history from samples collected between 1949 and 1955 inclusive on the California Cooperative Oceanic Fisheries Investigations (CalCOFI) grid. Despite wide broadcasting sf larvae, he concluded that gyres and countercurrents must retain larvae to ensure recruitrnent to the population. The conclusions are reviewed and the data reinterpreted in light of both recent physical oceanographic information and congeneric biology. Phyllosome concentrations are highly aggregated within the California Current: 66% of the larvae were located in 12% of the areal distribution, with the concewtrations located off central Baja California. Stage I larvae coocc~lrred nearshore in areas of moderate Ekman wind drift. They were quickly (about 1 3 d) transported southward, likely by the California Current, to a perennially occurring, semipermanent gyre. Phyllosornematuration to stage Vlll occurred over a 5-mo period within the gyre. Late-stage ( I X - X I ) concentrations occurred slightly northwest of the gyre, possibly transported by the connterflowing Davidson Ceerrent. Pueruli were rarely encountered, suggesting a deepwater (>I40rn) distribution. Onshore movement is likely made by the puerulus stage. Phyllossme concentrations in the Southern California Bight were rare (stage O only). Evidence is presented to support the hypothesis that recruitment to this northern, V relatively impoverished brood stock area may be episodic, influenced by the Barge-scale, interannual El Nirio events. Le regrette Br M. W. Johnson a etudie Ifhistoire naturelle des larves de phyllosomes de Panulirus interruptus 2 partir dfi.chantillons recueillis entre 1949 et 1955 inciusivement, sur une grille des California Cooperative Oceanic Fisheries Investigations (CALCOFI). Malgre une vaste dispersion des larves, il a conclu que des tsurbilloms oceaniques et des contre-courants doivent retewir les larves pour assurer le recrutement dans la population. O n examine les c~nclusions on rbinterprete 6 s dsnn6es en tenant cornpte des informations recentes et e sur l'oceanragraphie physique et la biolsgie des cowgbn6res. Les concentrations de phyl~osornes sont tres agglomerees A B'interieur du courant de Californice: 64 % des Iarves ktaient Iocalis&s dans 12 % de la distribution supedicielle, les concentrations se trouvant situees au large de la partie centrale de la Basse-Californie, Des larves du stade I se retrouvaient ensemble pres des c8tes dans les secteurs de la derive rnsd&r$e due au vent drEkman. Elks ont 6te transport6es rapiderrsent (environ 13 j ) au sud, vraisemblablement par le courant de Califsrwie, vers un tourbillon oceanique semi-permanent se produisant perp5tuellement. La maturation des phyllosomes au stade VIII sfest produite sur une pbriode de 5 r o 2 Irint6rieur du tourbillon. Les concentrations des derniers stades m larvaires (IX->(I]se sont produites IegPrement au nord-suest du tourbillon, tramportees probablement par le courant Davidson qui c o d e en sens inverse. O n a rencontre rarement des puerulus, ce qui laisse supposer uwe distribution en eaux profondes ( > I 40 m). Le mouvernent pres de la c6te est probablement dO 2 des individus du e stade puerulus. bes concentrations d e phyllosornes aa sud de la baie de CaBifornie ont &t& rares (stade I$/ seulement). Bes preuves sont prksentees pour appuyer Ifhypothese vcpulant que le recrutement dans ce secteur nord, relativement pauvre, de reproducteurs ssit epiwdique, influenci. par B s phenornt?wes de grande envergure e interawwuels du courant Ei Nirio.
Received ju/y 15, 6 986 Accepted june 65, 3986
he Hate Dr. Martin Johnson was one of the cofounders of oceanography's multidisciplinary approach (Svedmp et al. 1942), now an integral part of this science (McGowan and Brinton 1985). He maintained that one cannot separate in situ changes from advective events when studying dynamic oceanic processes. The California Current flora and fauna were frequently found to be a mixture of species of external origin. The concept that physical oceanography has a major influence on plankton biology and ecology was then developed. Johnson (1954) went further when he suggested that physical variables were of even greater influence on plankton population denslay and community structure than were food Bimitation, energy flow, and competitive interaction. Dr. Johnson, late in his career, was challenged by the
enigma of the spatial and temporal distribution in the California Current sf the California spiny lobster (Panulirus interruptus (Randall)) phylloscsrne larvae. He delivered in the early 1950's a broad and skillful oceanographic background to the study of this problem (McGowan and Brinton 1985). A fixed grid of stations had been set up in 1949 in the California Current by California Cooperative Oceanic Fisheries lnvestigations (CalCOFI). Biological samples and hydrographic measurements were made monthly (1949-60) from two to three vessels (the stations have been sampled less frequently since 1960). This was the source of Dr. Johnson's data (Johnson 1956, 1968a, 19Wb). Surprisingly, little work has since been done on the phyllosome ecology of P . interreaptus, given its economic imCan. J . Fish. Aquur. Seb., Vo!. 43, 1986
FIG. I . Distribution of P . knlerrup~us phyllosome larvae captured on the CalCOFI grid during 1949-55 inclusive (data from Johnson 1960a). Note that 66.1% of the Bawrae occurred in 82% of the areal distribution.
prtance, particularly in noflhwestem Mexico. Advances have been made in both the biology of congenerics (particularly B. c'ygpaus) and the physical oceanography of the California Current. Dr. Johnson's data and concIusions are reviewed here in the light of this more recent knowledge. Emphasis is placed on extending our understanding of larval retention and recmitment in this system.
Review ( ~Data, Hypotheses, and Concepts f~ ~ for D ~ .~~h~~~~~~Conclusions in ~ ~~~~l ~ k ~ Advestion Adult P. interruptus ranges from Monteray Bay, California,Can. J . Fish. Aqusat. Sci., Val. 4 3 , 1986
(rare north of Pt. Conception) to Magdalena Bay, Mexico (Fig. I); central Baja California (Mexico) is the center of aburadance (Johnson 1960a). Commercial exploitation began in 1872 (F. Odemar, California Department of Fish and Game, Long Beach, CA, pers. cornrn.) and a commercial trap fishery now exists throughout the species rznge (Duffy 1973). California State lobster fishing regulations were introduced in 1901 (F. Odemar, pers. cornrn.). Shortly afterward, Allen ( 1916) appealed for a full biological understanding of this species. Forty years later, Johnson (1956) made a similar appeal after ~ what appeared to be an acceptance of Lindberg's (f955) chal~ ~ d lenge that the larvae were the " . . . keystone of the population . . . and about the larval stage little is known." CalCOFl personnel collected hundreds of plankton samples.2143
I l l
FIG. 2. Estimated stage duration and temporal wcunence sf P . irrrerreepaus phyllssome larvae ((data from Johnson 1960a).
Hauls were made with a conical net, 1 x 5 m, with mesh apertures of 0.65 mm, finer at the codend. Tows were made from depth (from 70 rn before B 95 1 and from 148 m after 1951) at a rate of approximately 14 rn man-', with a tow angle of 45". Samples from 75 cruises between 1949 and 1955 (inclusive) were sorted and 3287 phyllosomes recovered (Johnson 1960a, E960b). These low numbers tended to refute Lindberg's (1955) contention that the larvae must be common given the large reproductive potential of the species. Eleven " . . rather poorly defined stages . . ." were described (Johnson 19561, of which "The intermediate stages are not always clear-cut . . . The first, second, tenth and eleventh stages are . . . well defined." (Johnson H 964%). Stage duration is plotted with time (Fig. 2). Johnson (196Oa) concluded that the time to metamorphosis (puerulus stage) was approximately 230 d. He attempted to discern recruitment processes by plotting horizontal larval distribution with geostrophic flows (steric height data were collected simultaneously with the larvae). Little was known in the 1950's about the vertical distribution of palinurid larvae. Johnson 6 1956) suggested that the scarcity of the larvae may indicate a tendency to seek levels near the bottom. Indeed, he noted that a bottom drag had captured a number of stage 19snear shore. Lindberg (1955) claimed that Scripps' personnel captured more .phyllosomes between 200 and 1200 fathoms than at the surface (unpubl. data). Similarly. Gurney (1936) claimed that the '"Thor" and '6DDiscovery" samples exhibited only late-stage phyllosomes (". . . high sea f o m s . . .") which were " . . . apparently confined to the deeper layers . . . ." Other workers, however, suggested that phylBosomes of the rock lobster, P. vulgaris, were either surface dwelling (Cunningham 1892) or exhibited diurnal vertical movement, being more frequent at the surface during darkness (Russel 1923-25). Harada ( 1957) noted that P. japonica phyllosomes were more abundant at the surface at dawn and less abundant after sunrise. Johnson (1960b) noted that 57% of the larvae were captu