Pro Delphinus

Lima, Peru

Pro Delphinus

Lima, Peru
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Vianna J.A.,Andrés Bello University | Vianna J.A.,University of Santiago de Chile | Ayerdi P.,Andrés Bello University | Ayerdi P.,University of Santiago de Chile | And 3 more authors.
Journal of Heredity | Year: 2010

The evolutionary history of a species can be revealed by phylogeographical analysis; nevertheless, not only historical but also contemporary processes can imprint on the distribution of genetic diversity. We report on the phylogeny of Lontra ssp. in South America, and the role of spatial heterogeneity in shaping the distribution and population structure of the endangered marine otter, Lontra felina. Analyzing a total of 2261 bp of mitochondrial DNA (mtDNA) revealed the recent divergence of L. felina from L. provocax. A strong population structure (Φst = 0.83, P < 0.0001) and a significant pattern of isolation by distance were described for L. felina (n = 168) across a wide geographical distribution (13°53′S to 43°36′S). Lontra felina mtDNA phylogeny is composed of 2 main clades: a clade from Peru and another composed of Chilean haplotypes. Northern populations show different divergent lineages and higher genetic diversity when compared with more recently colonized southern populations. Furthermore, long sandy beaches seem to act as barriers to dispersal, creating 2 evolutionary significant units in agreement with subspecies previous description, and at least 5 different management units (MUs). At a fine spatial scale, the size of rocky seashore patches, the distance between patches and anthropogenic factors also play important roles in species gene flow. © 2010 The American Genetic Association. All rights reserved.

Pajuelo M.,University of Florida | Bjorndal K.A.,University of Florida | Alfaro-Shigueto J.,Pro Delphinus | Alfaro-Shigueto J.,University of Exeter | And 4 more authors.
Marine Ecology Progress Series | Year: 2010

Denitrification and nitrogen-fixation processes in the marine environment have been intensively studied, particularly how these processes affect the nitrogen stable-isotope signature (δ15N) of inorganic nutrients and organisms at the base of the food web. However, the assumption that these δ15N differences at the base of food webs are reflected in higher trophic-level organisms has not been widely investigated. In the present study, we evaluated whether an ocean-basin δ15N variation was evident in oceanic juvenile loggerhead turtles Caretta caretta by analyzing their stable-isotope signatures in the Pacific and Atlantic oceans. Skin samples from oceanic juvenile loggerheads were collected from Peruvian waters in the southeast Pacific and from waters around the Azores Archipelago in the northeast Atlantic and analyzed for δ15N and carbon stable-isotope signature (δ13C). Our results showed that turtles in the 2 ocean regions have mean δ13C signatures of -16.3 and -16.7 %o, which reflects the oceanic feeding behavior of these loggerhead populations. However, the δ15N signatures in Pacific loggerheads are significantly higher (mean ± SD = 17.1 ± 0.9%o) than those of Atlantic loggerheads (7.6 ± 0.5%o). This inter-ocean difference in δ15N values was also observed in organisms at the base of the food web in the 2 study areas. The δ15N at the base of the food web, which is determined by the predominant process of the nitrogen cycle in each ocean region, is subsequently transferred to higher trophic levels. Stable isotope signatures in high trophic-level organisms, such as oceanic-stage sea turtles, can reveal differences in oceanographic processes. © Inter-Research 2010.

Tzika A.C.,University of Geneva | Tzika A.C.,Roosevelt University | D'Amico E.,Free University of Colombia | Alfaro-Shigueto J.,Pro Delphinus | And 5 more authors.
Conservation Genetics | Year: 2010

In the last 60 years, incidental entanglement in fishing gears (so called by-catch) became the main cause of mortality worldwide for small cetaceans and is pushing several populations and species to the verge of extinction. Thus, monitoring and quantifying by-catches is an important step towards proper and sustainable management of cetacean populations. Continuous studies indicated that by-catches and directed takes of small cetaceans in Peru greatly increased since 1985. Legal measures banning cetacean takes, enforced in 1994 and 1996, ironically made monitoring highly problematic as fishers continue catching these animals but utilize or dispose of carcasses clandestinely. Hence, in locations where cetaceans are landed covertly or already butchered, molecular genetic methods can provide the only means of identification of the species, sex, and sometimes the population of each sample. Here, we generate and analyse a fragment of the mitochondrial DNA cytochrome b gene and 5 nuclear microsatellite markers from 182 meat and skin samples of unidentified small cetaceans collected at three Peruvian markets between July 2006 and April 2007. Our results, compared to past surveys, indicate that Lagenorhynchus obscurus, Phocoena spinipinnis, Tursiops truncatus, Delphinus capensis, and D. delphis continue to be caught and marketed, but that the relative incidence of P. spinipinnis is highly reduced, possibly because of population depletion. The small number of possible sampling duplicates demonstrates that a high monitoring frequency is required for a thorough evaluation of incidental catches in the area. A wide public debate on by-catch mitigation measures is greatly warranted in Peru. © 2010 Springer Science+Business Media B.V.

Benavides M.T.,Marine Conservation Institute | Feldheim K.A.,Pritzker Laboratory for Molecular Systematics and Evolution | Duffy C.A.,Aquatic and Threats Unit | Wintner S.,KwaZulu Natal Sharks Board | And 14 more authors.
Marine and Freshwater Research | Year: 2011

The copper or bronze whaler shark (Carcharhinus brachyurus) is a large, coastal top predator that is vulnerable to overexploitation. We test the null hypothesis that copper sharks are panmictic throughout the southern hemisphere. We analysed part of the mitochondrial control region (mtCR) in 120 individuals from eight sampling areas, defining 20 mtCR haplotypes (h = 0.76 ± 0.06, π = 0.016 ± 0.0007). Significant genetic structure was detected among the following three major coastal regions separated by oceanic habitat: Australia-New Zealand, South Africa-Namibia and Per (AMOVA Φ ST=0. 95, P < 0.000001). A major phylogeographic discontinuity exists across the Indian Ocean, indicating an absence of at least female-mediated gene flow for ∼3 million years. We propose that this species originated in the Atlantic, experienced vicariant isolation of Pacific and Atlantic lineages by the rise of the Isthmus of Panama and, subsequently, dispersed across the Pacific to colonise Australasia. Oceanic expanses appear to be traversed over evolutionary but not ecological timescales, which means that regional copper-shark populations should be assessed and managed independently. © CSIRO 2011.

Alfaro-Shigueto J.,University of Exeter | Mangel J.C.,University of Exeter | Bernedo F.,Pro Delphinus | Dutton P.H.,Southwest Fisheries Science Center | And 2 more authors.
Journal of Applied Ecology | Year: 2011

1. Over the last few decades, evidence of marine vertebrate bycatch has been collected for a range of industrial fisheries. It has recently been acknowledged that large impacts may also result from similar interactions with small-scale fisheries (SSF) due largely to their diffuse effort and large number of vessels in operation. Marine mammals, seabirds, turtles as well as some shark species have been reported as being impacted by SSF worldwide. 2. From 2000 to 2007, we used both shore-based and onboard observer programmes from three SSF ports in Peru to assess the impact on marine turtles of small-scale longline, bottom set nets and driftnet fisheries. 3. We reported a total of 807 sea turtles captured, 91·8% of which were released alive. For these three sites alone, we estimated c. 5900 turtles captured annually (3200 loggerhead turtles Caretta caretta, 2400 green turtles Chelonia mydas, 240 olive ridleys Lepidochelys olivacea and 70 leatherback turtles Dermochelys coriacea). 4.SSF in Peru are widespread and numerous (>100 ports, >9500 vessels, >37000 fishers), and our observed effort constituted c. 1% of longline and net deployments. We suggest that the number of turtles captured per year is likely to be in the tens of thousands. Thus, the impacts of Peruvian SSF have the potential to severely impact sea turtles in the Pacific especially green, loggerhead and leatherback turtles. 5. Implications of the human use of turtle products as 'marine bushmeat' are also raised as an important issue. Although such utilization is illegal, it is difficult to foresee how it can be managed without addressing the constraints to the livelihoods of those depending almost entirely on coastal resources. 6. Syntheses and applications. Our analysis demonstrates that, despite logistical challenges, it is feasible to estimate the bycatch per unit of effort in SSF by combining methods that account for fishing effort and bycatch, such as using onboard and shore-based observers. We highlight sea turtle bycatch in SSF in the southeast Pacific as a major conservation concern but also suggest possible paths for mitigation. © 2011 The Authors. Journal of Applied Ecology © 2011 British Ecological Society.

Mangel J.C.,Pro Delphinus | Mangel J.C.,University of Exeter | Alfaro-Shigueto J.,Pro Delphinus | Alfaro-Shigueto J.,University of Exeter | And 4 more authors.
Marine Ecology Progress Series | Year: 2011

The post-capture movements made by loggerhead sea turtles Caretta caretta in the southeastern Pacific Ocean were monitored from 2003 to 2007. Fourteen loggerhead turtles were fitted with satellite transmitters and released off the coast of Peru. All turtles were juveniles (curved carapace length range: 40.5 to 68.5 cm) incidentally captured by small-scale longline fishing vessels from southern or central Peru. Track durations were highly variable (mean ± SD: 143 ± 90 d; range: 8 to 297 d) with no clear signs of immediate post-release mortality. Upon release, all turtles moved offshore beyond the continental shelf. Eight of 11 turtles tracked for <60 d had final displacements of >750 km, suggesting that loggerhead turtles often maintain extended residency in these waters and that this area is an important foraging zone for loggerhead turtles of southwest Pacific origin. Satellite tracks also showed a substantial overlap of areas used by turtles with known Peruvian longline fishing effort. Turtles spent 75% of their time within the area fished by this fleet (based upon observed sets). This suggests that turtles are vulnerable to fishery interactions and that bycatch mitigation measures should be employed to minimize fishery impacts on loggerhead turtles. The loggerhead turtles tracked during this study spent ca. 51% of their time in Peruvian waters, 39% in international waters and 9% in Chilean waters, which emphasizes the need for a multinational approach to sea turtle conservation and fisheries management in the region. © 2011 Inter-Research.

Alfaro-Shigueto J.,University of Exeter | Mangel J.C.,University of Exeter | Pajuelo M.,Pro Delphinus | Dutton P.H.,Southwest Fisheries Science Center | And 2 more authors.
Fisheries Research | Year: 2010

Small-scale fisheries in Peru constitute an important source of food and employment for coastal communities where fish is the single most important natural resource. Utilizing official statistics and extensive survey data from 30 fishing ports and by onboard observers operating from 11 ports, we review how these fisheries grew from 1995 to 2005, and provide insights into the relative importance of different fishing gears and their modes of operation. Small-scale fisheries operate along the entire Peruvian coast and have continued expanding in number of vessels and fishers in all geopolitical regions except one. Nationwide, the number of fishers grew by 34% from 28. 098 to 37. 727 and the number of vessels increased by 54% from 6268 to 9667. At 30 harbors, the number of vessels increased for purse seiners (17.8%) and longliners (357.4%), while gillnets decreased (-14.5%). These dramatic changes could jeopardize the sustainability of these fisheries and the livelihoods of those who depend upon them, especially considering the limited capacity for management. Despite increase in effort, catch and catch per vessel have decreased, especially in some of the sub-regions that previously constituted the majority of effort and landings, raising concerns regarding their sustainability. Of the fishing gears monitored, gillnets were shown to have the most frequent interactions with threatened taxa such as marine mammals, seabirds and sea turtles. The total length of gillnets set in Peru was estimated at >100. 000. km of net per year, about 14 times the length used by the Taiwanese high seas driftnet fleet in the Pacific before it was banned. Longlines, although shown to be a more efficient fishing method (economically and in terms of selectivity), still had bycatch of turtles and seabirds, and marine mammals are targeted to be used as bait. We conservatively estimate that longline vessels operating in Peru set an average of 80 million hooks per year; equivalent to one-third of the annual effort of the global industrial swordfish longline fishery. We conclude that, despite their definition as small-scale, the magnitude of these fleets and their fishing effort are vast and are of concern with regard to their long term sustainability and their impacts and interactions with large marine vertebrates. We highlight the need for increased research and management measures to ensure the long term viability of these fisheries. © 2010 Elsevier B.V.

Alfaro-Shigueto J.,Pro Delphinus | Alfaro-Shigueto J.,University of Exeter | Alfaro-Shigueto J.,Scientific University of the South | Mangel J.C.,Pro Delphinus | And 3 more authors.
Pan-American Journal of Aquatic Sciences | Year: 2016

The waved albatross Phoebastria irrorata is classified by the IUCN as "critically endangered" because of its geographically restricted breeding range and evidence of a substantial decline in adult survival during the 1990s and early 2000s. This decline has been proposed to be a consequence of incidental mortality in the Peruvian small-scale fisheries but also of direct hunting for human consumption by fishermen. This paper uses a trans-disciplinary approach to describe and analyse the intentional capture of waved albatrosses in northern Peru by offshore small-scale fishermen. During 2008, 36 interviews were conducted in the port of Salaverry to understand the extent and reasons for the intentional capture. Sixty-nine precent of the interviewees mentioned occasionally harvesting albatrosses. Considering two to three vessels capture albatrosses regularly in Salaverry, we estimate a total annual mortality between 16 and 24 individuals since 2006. Reasons for capturing albatrosses included insufficient food supplies onboard during long fishing trips, collection of rings from ringed birds, the development of a taste for the bird's meat and even boredom. Interviews with fishermen showed a lack of awareness of the conservation status of albatrosses. We recommend strengthening the role of existing local governmental and non-governmental organizations involved with monitoring and surveillance, education and conservation.

Mangel J.C.,Pro Delphinus | Mangel J.C.,University of Exeter | Alfaro-Shigueto J.,Pro Delphinus | Alfaro-Shigueto J.,University of Exeter | And 5 more authors.
Biological Conservation | Year: 2010

We detail the first direct, at sea monitoring of small cetacean interactions with Peruvian artisanal drift gillnet and longline fisheries. A total of 253 small cetaceans were captured during 66 monitored fishing trips (Gillnet: 46 trips; Longline: 20 trips) from the port of Salaverry, northern Peru (8o14′S, 78o59′W) from March 2005 to July 2007. The most commonly captured species were common dolphins (Delphinus spp.) (47%), dusky dolphins (Lagenorhynchus obscurus) (29%), common bottlenose dolphins (Tursiops truncatus) (13%) and Burmeister's porpoises (Phocoena spinipinnis) (6%). An estimated 95% of common dolphin bycatch was of long-beaked common dolphins (Delphinus capensis). Overall bycatch per unit effort for gillnet vessels (mean ± sd) was estimated to be 0.65 ± 0.41 animals.set-1 (range 0.05-1.50) and overall catch (bycatch and harpoon) was 4.96 ± 3.33 animals.trip-1 (range 0.33-13.33). Based upon total fishing effort for Salaverry we estimated the total annual average small cetacean bycatch by gillnet vessels as 2412 animals.year-1 (95% CI 1092-4303) for 2002-2007. This work indicates that, in at least one Peruvian port, bycatch and harpooning of small cetaceans persist at high levels and on a regular basis, particularly in driftnet vessels, despite the existence since the mid-1990s of national legislation banning the capture of marine mammals and commerce in their products. It is concluded that the coast of Peru is likely still one of the world's principal areas for concern regarding high small cetacean bycatch and there is clearly an urgent need to increase the geographic scope of observer effort to elucidate the full magnitude of this issue. © 2009 Elsevier Ltd. All rights reserved.

Mangel J.C.,Pro Delphinus | Mangel J.C.,University of Exeter | Whitty T.,University of California at San Diego | Medina-Vogel G.,Andrés Bello University | And 3 more authors.
Marine Mammal Science | Year: 2011

The marine otter (Lontra felina) inhabits patches of rocky coastline from central Peru to southern Chile and is classified as Endangered by the IUCN. Given the limited information available about the species, we set out to assess marine otter diet with a view to detecting latitudinal differences, and to assess marine otter activity budgets and interspecific interactions (including anthropogenic) at Peruvian fishing villages and to compare results with similar Chilean studies. Nine study sites from central Chile to southern Peru were sampled for otter spraints to assess relative frequency of prey types and two fishing ports in southern Peru were monitored through focal and scan observations to assess activity patterns, interspecific interactions, habitat use patterns, and dive durations. Results indicate that toward the northern part of its range, crustaceans become less important and fish more important in the diet. Interactions were observed between marine otters and other species, including stray dogs and cats. The strong dependence of marine otters on the availability of safe rocky shelters, and the species' apparent tolerance to living alongside humans raise conservation concerns about vulnerability to anthropogenic threats. These factors, if not correctly managed, could turn some of these rocky seashore patches into population sinks. © 2010 by the Society for Marine Mammalogy.

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