Catch and bycatch of sea birds and marine mammals in the small-scale fishery of Punta San Juan, Peru

Patricia Majluf, Elizabeth A Babcock, Juan Carlos Riveros, Milena Arias Schreiber, William Alderete

Research output: Contribution to journalArticle

48 Citations (Scopus)

Abstract

Between 1991 and the present, we have had observers stationed at the port of San Juan in southern Peru to interview fishers as they landed their catch. They observed the landings of 922 Humboldt Penguins (Spheniscus humboldti), 510 dusky dolphins (Lagenorhynchus obscurus), 214 Burmeister's porpoises (Phocaena spinnipinnis), and 75 bottlenose dolphins (Tursiops truncatus,) between November 1991 and June 1998, although the retention of penguins and small cetaceans is banned by Peruvian law. Most of these animals were captured in 1992-1994, when the fishers were mainly using surface-drift gillnets to target a pelagic schooling fish called cojinova (Seriolella violacea). Capture rates were much lower in 1995-1998, when fishers were mostly using fixed demersal gillnets and shellfish diving, due apparently to a lack of surface-schooling cojinova in the vicinity. We used generalized linear models to examine the effect of year, gear type, area, and target fish species on the probability of capturing either penguins or dolphins. We found that the probability of a fishing vessel capturing a penguin or a dolphin increased when drift gillnets were used instead of fixed gillnets. Fishing area, year, and the species offish caught also significantly affected the probability of capture. A population model (Vortex) applied to Humboldt Penguins showed that the high levels of mortality seen in the early 1990s are not sustainable and could lead to local extinction in a few years. The mortality levels seen in the late 1990s are more likely to be sustainable, but a return to the use of drift gillnets would rapidly result in unsustainable levels of mortality.

Original languageEnglish
Pages (from-to)1333-1343
Number of pages11
JournalConservation Biology
Volume16
Issue number5
DOIs
StatePublished - Oct 1 2002
Externally publishedYes

Fingerprint

gillnet
Mammals
Fisheries
gillnets
Birds
marine mammal
marine mammals
penguins
bycatch
seabird
seabirds
Peru
dolphin
fishery
fisheries
Fish
dolphins
Fishing vessels
Shellfish
Tursiops truncatus

ASJC Scopus subject areas

  • Ecology
  • Environmental Science(all)
  • Environmental Chemistry
  • Nature and Landscape Conservation

Cite this

Catch and bycatch of sea birds and marine mammals in the small-scale fishery of Punta San Juan, Peru. / Majluf, Patricia; Babcock, Elizabeth A; Riveros, Juan Carlos; Schreiber, Milena Arias; Alderete, William.

In: Conservation Biology, Vol. 16, No. 5, 01.10.2002, p. 1333-1343.

Research output: Contribution to journalArticle

Majluf, Patricia ; Babcock, Elizabeth A ; Riveros, Juan Carlos ; Schreiber, Milena Arias ; Alderete, William. / Catch and bycatch of sea birds and marine mammals in the small-scale fishery of Punta San Juan, Peru. In: Conservation Biology. 2002 ; Vol. 16, No. 5. pp. 1333-1343.
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