Intestinal Parasites in Galapagos Sea Lions (Zalophus wollebaeki) Sivertsen, 1953 on San Cristóbal Island, Galapagos, Ecuador

Abstract This study examined knowledge of sea lions (Zalophus wollebaeki) for both residents and tourists on San Cristóbal Island in the Galápagos, a famous nature tourism destination. Participants (N = 281) obtained through convenience and snowball sampling answered questionnaires about their knowledge of sea lions. Participants with higher education received higher overall scores, but participants’ education and age influenced answers on only a few questions. Residents and tourists obtained comparable overall scores, exhibiting extensive knowledge of sea lion behavior and life history. Whether participants were residents or tourists influenced answers to several questions, but when only participants with 13 years of education or more were examined, few differences in answers remained between residents or tourists. Participants’ broad knowledge of sea lions may be attributed to the items of knowledge tested, participants’ motivations for travel to the Galápagos, and the fact that sea lions are an engaging and ubiquitous animal.

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PUP MORTALITY AND EVIDENCE FOR PATHOGEN EXPOSURE IN GALAPAGOS SEA LIONS (ZALOPHUS WOLLEBAEKI) ON SAN CRISTOBAL ISLAND, GALAPAGOS, ECUADOR

Journal of Wildlife Diseases ◽

10.7589/2016-05-092 ◽

2017 ◽

Vol 53 (3) ◽

pp. 491-498 ◽

Cited By ~ 6

Author(s):

Judith Denkinger ◽

Nataly Guevara ◽

Sofia Ayala ◽

Juan Carlos Murillo ◽

Maximilian Hirschfeld ◽

...

Keyword(s):

Sea Lions ◽

Zalophus Wollebaeki ◽

Pup Mortality ◽

Pathogen Exposure

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Spatial variation in the foraging behaviour of the Galapagos sea lions (Zalophus wollebaeki) assessed using scat collections and stable isotope analysis

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531541300163x ◽

2013 ◽

Vol 94 (6) ◽

pp. 1099-1107 ◽

Cited By ~ 12

Author(s):

Diego Páez-Rosas ◽

David Aurioles-Gamboa

Keyword(s):

Feeding Habits ◽

Isotope Analysis ◽

Space Time ◽

Trophic Niche ◽

Foraging Strategies ◽

Scat Analysis ◽

Sea Lions ◽

Fluctuating Resources ◽

Zalophus Wollebaeki ◽

Time Changes

This study focuses on the comparative analysis of variables related to the trophic niche plasticity in the Galapagos sea lion (Zalophus wollebaeki). There is great concern regarding the future of this species, so study of the diet and the way these animals obtain their food is useful to understand and predict their survival possibilities in the long term. The combined use of scat analysis and stable isotopes helps to determine foraging habits of this species in greater detail. The objective of the study was to assess the feeding habits of Z. wollebaeki and its space–time variation. The scat analysis (n = 200) gave as a result space–time changes in the foraging strategies of this species. The isotopic values (n = 80) showed differences in relation to foraging grounds (δ13C: P = 0.001), but also suggested an apparent stability in the trophic level of their diet (δ15N: P = 0.084). These results constitute a relevant finding in the evolutionary behaviour of the species, showing that Z. wollebaeki has developed a high degree of plasticity in its foraging habits that may improve its survival in a highly demanding ecosystem in terms of limited and fluctuating resources.

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Influence of hunting strategy on foraging efficiency in Galapagos sea lions

PeerJ ◽

10.7717/peerj.11206 ◽

2021 ◽

Vol 9 ◽

pp. e11206

Author(s):

Jessica-Anne Blakeway ◽

John P.Y. Arnould ◽

Andrew J. Hoskins ◽

Patricia Martin-Cabrera ◽

Grace J. Sutton ◽

...

Keyword(s):

Energy Consumption ◽

Energy Expenditure ◽

Foraging Strategy ◽

Foraging Strategies ◽

Foraging Efficiency ◽

Flat Bottom ◽

Sea Lions ◽

Dive Behaviour ◽

Zalophus Wollebaeki ◽

Depth Ranges

The endangered Galapagos sea lion (GSL, Zalophus wollebaeki) exhibits a range of foraging strategies utilising various dive types including benthic, epipelagic and mesopelagic dives. In the present study, potential prey captures (PPC), prey energy consumption and energy expenditure in lactating adult female GSLs (n = 9) were examined to determine their foraging efficiency relative to the foraging strategy used. Individuals displayed four dive types: (a) epipelagic (<100 m; EP); or (b) mesopelagic (>100 m; MP) with a characteristic V-shape or U-shape diving profile; and (c) shallow benthic (<100 m; SB) or (d) deep benthic (>100 m; DB) with square or flat-bottom dive profiles. These dive types varied in the number of PPC, assumed prey types, and the energy expended. Prey items and their energetic value were assumed from previous GSL diet studies in combination with common habitat and depth ranges of the prey. In comparison to pelagic dives occurring at similar depths, when diving benthically, GSLs had both higher prey energy consumption and foraging energy expenditure whereas PPC rate was lower. Foraging efficiency varied across dive types, with benthic dives being more profitable than pelagic dives. Three foraging trip strategies were identified and varied relative to prey energy consumed, energy expended, and dive behaviour. Foraging efficiency did not significantly vary among the foraging trip strategies suggesting that, while individuals may diverge into different foraging habitats, they are optimal within them. These findings indicate that these three strategies will have different sensitivities to habitat-specific fluctuations due to environmental change.

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