Fenómeno Del Niño- Migración De Tortugas

Hydrobiologia (2010) 645:69–79
DOI 10.1007/s10750-010-0225-8

JELLYFISH BLOOMS

˜
Effects of El Nino-driven environmental variability on black
turtle migration to Peruvian foraging grounds
´
˜ones • Victoria Gonzalez Carman •
Javier Quin
Jorge Zeballos • Sara Purca • Hermes Mianzan

Published online: 21 March 2010
Ó Springer Science+Business Media B.V. 2010

Abstract We analyzedsea temperature as an environmental factor, in association with ENSO, affecting
the migration of East Pacific black turtle, Chelonia
mydas (=Chelonia agassizii Bocourt), to its foraging
´
areas and its feeding ecology at San Andres, Peru.
A 19-year sea turtle landing database (1970–1988)
was constructed to associate landing fluctuations with
environmental variability represented by thePeruvian
Oscillation Index. A positive correlation between
them (r = 0.75, P \ 0.05) indicated that exceptionally large black turtle landings occurred in San
´
˜
Andres port during El Nino episodes. Warmer waters
(SST 22–28°C) approached near the Peruvian coast

˜
during El Nino episodes, thus facilitating black turtle
˜
access to this area. Furthermore, during El Nino
1987, large juvenileand adult black turtles, known to
be primarily herbivorous, fed mainly on the scypho´
zoan jellyfish Chrysaora plocamia Peron & Lesueur,
which was very abundant during this event. It is
likely that black turtles exploited this resource
opportunistically. Inter-annual environmental vari˜
ability, driven by El Nino Southern Oscillation, has
profound consequences for the ecology of theendangered black turtle, which should be considered
when evaluating the effects of anthropogenic activities on its population dynamics.

Guest editors: J.E. Purcell & Dror Angel / Jellyfish Blooms:
New Problems and Solutions

Keywords Chelonia mydas (=Chelonia agassizii) Á
ENSO Á Trophic migration Á Jellyfish Á
Sea turtle landings Á Peru

˜
J. Quinones Á J. Zeballos
´
Laboratorio Costero dePisco, Instituto del Mar del Peru
(IMARPE), Av. Los Libertadores A-12, Urb. El Golf,
Paracas, Ica, Peru
e-mail: javierantonioquinones@gmail.com
´
V. Gonzalez Carman Á H. Mianzan (&)
´
CONICET-Instituto Nacional de Investigacion y
Desarrollo Pesquero (INIDEP), Paseo Victoria Ocampo
n°1, B7602HSA Mar del Plata, Argentina
e-mail: hermes@inidep.edu.ar
S. Purca
´
Centro de Investigaciones enModelaje Oceanografico y
´
´
Biologico-Pesquero (CIMOBP), Instituto del Mar del Peru
(IMARPE), Esquina Gamarra y General Valle s/n
Chucuito, Callao, Peru

Introduction
The coastal ecosystem off Peru and Chile is characterized by strong, persistent wind-driven upwelling of
nutrient-rich waters. This upwelling sustains high
biological productivity and supports one of the
world’s largestsingle-species fisheries (Chavez
et al., 1999, 2008; Pennington et al., 2006). Oceanographic and atmospheric conditions fluctuate on
seasonal to inter-decadal scales (Wyrtki, 1975; Tourre
et al., 2005). Among such variations, inter-annual
˜
variability due to the El Nino Southern Oscillation
(ENSO) is known to affect physical, chemical, and

123

70

nutritional conditions of the ocean(Fiedler et al.,
´
1991; Chavez et al., 1999; Ayon et al., 2004). During
an ENSO, the equatorial zonal winds weaken, thus
driving an upwelling of warmer waters due to a
deeper-than-normal main thermocline (Ji & Leetmaa,
1997). Biological responses to this phenomenon are
exhibited by a wide variety of organisms. For
example, primary production is severely reduced
(Barber & Chavez, 1983) andlarge amounts of
benthic macroalgae wash ashore during the strongest
ENSO (i.e., 1982–1983). The latter affects the related
benthic and grazing fauna (Tarazona et al., 1988;
Arntz & Fahrbach, 1996; Fernandez et al., 1999).
Furthermore, anchovy (Engraulis ringens Jenyns)
concentrates in shallower refuge waters (Csirke,
1989; Muck et al., 1989a; Arntz & Fahrbach, 1996)
where a large die off...