Distribution and Habitat Use of a Cryptic Small Cetacean, the Burmeister's Porpoise, Monitored From a Small-Scale Fishery Platform

There is widespread evidence that small-scale fisheries (SSF) bycatch threatens many populations of small cetaceans, yet conservation efforts are often limited by a lack of basic knowledge regarding their abundance, distribution, and habitat use. Here, we used passive acoustic monitoring from an SSF platform-of-opportunity to better characterize the distribution and habitat use of small cetaceans in northern Peru, focussing on the little-known Burmeister's porpoise Phocoena spinipinnis. From 2009 to 2012, acoustic click detectors (C-PODs) were attached to fishing nets for the duration of 116 fishing sets (30 fishing trips). Dolphins (unspecified delphinids) and porpoises were recorded around 71 and 22% of fishing sets, respectively. The probability of occurrence and buzzing behavior (a proxy for foraging), and time spent, were linked to both static and dynamic environmental variables to examine the drivers of habitat use. Dolphin activity was spread evenly throughout the fishing area and was not linked to any habitat variables. In contrast, porpoises were detected in neritic waters, and habitat models performed well, identifying preferences for shallow (<200 m depth) and cooler (17–18°C) waters, close (<50 km) to shore. The high bycatch rate of small cetaceans in Peruvian SSF gave us the unique opportunity to investigate the link between bycatch and cetacean activity around vessels. We found a positive relationship between the likelihood of a bycatch event and acoustic presence for both dolphins and porpoises, however as we did not know the timing of entanglement, we could not link vocalization rates to mortality events. Nonetheless, as small cetaceans (particularly dolphins) frequently encounter fishing boats, the likelihood of entanglements may be reduced through effective efforts to alert animals to the presence of the net, either acoustically (using acoustic alarms) or visually. This study demonstrates that passive acoustic monitoring from a fisheries platform can provide insights into the distribution and habitat use of small cetaceans at relatively low cost, and is likely to be suitable in regions with low monitoring effort and high fishing pressure

Marine mammal conservation: over the horizon

Artículo escrito por más de 35 autores.Marine mammals can play important ecological roles in aquatic ecosystems, and their presence can be key to community structure and function. Consequently, marine mammals are often considered indicators of ecosystem health and flagship species. Yet, historical population declines caused by exploitation, and additional current threats, such as climate change, fisheries bycatch, pollution and maritime development, continue to impact many marine mammal species, and at least 25% are classified as threatened (Critically Endangered, Endangered or Vulnerable) on the IUCN Red List. Conversely, some species have experienced population increases/recoveries in recent decades, reflecting management interventions, and are heralded as conservation successes. To continue these successes and reverse the downward trajectories of at-risk species, it is necessary to evaluate the threats faced by marine mammals and the conservation mechanisms available to address them. Additionally, there is a need to identify evidence-based priorities of both research and conservation needs across a range of settings and taxa. To that effect we: (1) outline the key threats to marine mammals and their impacts, identify the associated knowledge gaps and recommend actions needed; (2) discuss the merits and downfalls of established and emerging conservation mechanisms; (3) outline the application of research and monitoring techniques; and (4) highlight particular taxa/populations that are in urgent need of focus

Ecology and Conservation of Sea Turtles in Peru

Some of the key elements to assess the status of any wildlife population in a given geographical area are the levels of recruitment, survival and mortality. Whilst most of the information on marine turtles has been obtained from nesting sites, turtles spend most of their lives at sea. The conservation status of marine turtles in the southeast Pacific is poorly documented. This is particularly true for countries like Peru, where nesting events are very rare, although five species of turtles from populations from all over the Pacific basin, use these waters as foraging grounds. Little information exists on the threats to turtle populations in foraging areas or the magnitude of these impacts. Small-scale fisheries are a globally important economic activity serving as a source of food and employment for ca. 1 billion people; however we show that they also have serious impacts on marine turtle populations from all over the Pacific basin in the form of incidentally captured marine turtles. The five chapters that constitute this thesis are intended to increase our understanding of small-scale fisheries impacts on this taxon during their aquatic life stages. This work focuses on describing these fisheries, their impacts on marine turtles and proposes methodologies to monitor and assess the level of bycatch from small-scale fisheries. We also discuss alternative ways to prevent fisheries interactions and promote the involvement of artisanal fishermen in the southeast Pacific in implementing conservation solutions

Resultados preliminares de valores gematológicos en una población silvestre de Spheniscus humboldti en el sur de Perú

The objective of this report was to present data on the hematological profile of the Humboldt penguin (Spheniscus humboldti) in Punta Coles, Peru. Values of hematocrit, white blood cell count and leukocyte formula were determined in four individuals. Blood samples (5 ml) were extracted by jugular puncture. The results were: hematocrit 44.5 ± 4.12%, white blood cell count 17.25 ± 4.57x10³/μl, heterophiles 9.85 ± 1.91x10³/μl, lymphocytes 3.7 ± 0.51x10³/μl, monocytes 1.52 ± 0.99x10³/μl, eosinophils 1.3 ± 0.51x10³/μl. The lymphocytes showed lower values than other wild and captive populations of S. humboldti.El objetivo de este reporte fue presentar datos sobre el perfil hematológico del pingüino de Humboldt (Spheniscus humboldti) en Punta Coles, Perú. Se realizaron evaluaciones sanitarias en las que se establecieron valores de hematocrito, recuento de leucocitos y fórmula leucocitaria en cuatro individuos. La sangre (5 ml) se extrajo mediante punción yugular. Los resultaron fueron: hematocrito 44.5±4.12%, recuento de glóbulos blancos 17.25±4.57x10³/μl, heterófilos 9.85±1.91x10³/μl, linfocitos 3.7±0.51x10³/μl, monocitos 1.52±0.99x10³/μl y eosinófilos 1.3±0.51x10³/μl. Los linfocitos presentaron valores más bajos que otras poblaciones silvestres y en cautiverio de S. humboldti

Molecular identification of small cetacean samples from Peruvian fish markets

In the last 60years, 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 Per

Mercury levels in the Smooth Hammerhead Shark Sphyrna zygaena (Carcharhiniformes: Sphyrnidae) from Northern Peru

El tiburón martillo (Sphyrna zygaena (Linnaeus, 1758)) es una de las especies de elasmobranquios más utilizada para consumo humano en el Perú. Sin embargo, se desconoce los niveles de mercurio que contiene su carne. Este trabajo tuvo como objetivo evaluar los niveles de mercurio hallados en el músculo del tiburón martillo y su posible implicancia en la salud humana. Además, determinar si existe una correlación entre el tamaño del tiburón y los niveles de mercurio. Analizamos 27 muestras de músculo de neonatos y juveniles capturados en el norte del Perú. La concentración de mercurio varió entre 0.13 – 0.85 mg kg-1 peso húmedo. Se encontró una relación negativa y significativa entre el tamaño corporal del tiburón y los niveles de mercurio. Este trabajo representa el primer estudio que evalúa los niveles de mercurio de tiburones en el Perú. Si bien los valores hallados fueron menores a lo recomendado por la Organización Mundial de la Salud (< 1 mg kg-1), se recomienda ampliar este tipo de estudios en individuos adultos de tiburón, así como en otros recursos hidrobiológicos de consumo humano.The smooth hammerhead shark Sphyrna zygaena (Linnaeus, 1758) is one of the elasmobranch species most used for human consumption in Peru. However, the level of mercury in hammerhead muscle tissue is unknown. This study assessed the level of mercury found in the muscle of hammerhead sharks and its relation with human health. Moreover, we evaluated the relationship between shark body size and mercury levels. We analyzed 27 muscle samples of neonates and juveniles captured in northern Peru. Mercury concentrations varied between 0.13 and 0.86 mg kg-1 wet weight. Moreover, we found a negative and significant relationship between shark body size and mercury levels. This study represents the first evaluation of mercury levels of sharks in Peru. Although the values found do not exceed levels recommended by the World Health Organization (< 1 mg kg-1), we recommend expanding this study to include other size classes of sharks as well as other marine resources used for human consumption

An evaluation of information sharing schemes to identify what motivates fishers to share catch information

Funding This work has been funded by Science Foundation Ireland through a Starting Investigator Research grant number 18/SIRG/5554.Peer reviewedPublisher PD

Small-scale fisheries of Peru: a major sink for marine turtles in the Pacific

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, 91Æ8% 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 (\u3e100 ports, \u3e9500 vessels, \u3e37 000 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

Batoid fishery in Peru (1950-2015): Magnitude, management and data needs: Pesquería de batoideos en Perú (1950-2015): Magnitud, manejo y necesidades de información

Historical landings from the Food and Agriculture Organization (1950–2015) were used to estimate the contribution of the Peruvian batoid fishery to the eastern Pacific Ocean, and species-specific landings from Instituto del Mar del Peru (1997-2015) were used to identify the most-landed species, their landings sites and monthly variation throughout the year, and fishing gear types most used. The regulatory and research landscape were evaluated toward identifying potential gaps that may be hindering conservation and management of batoids in Peru. Results showed that in the eastern Pacific, Peru ranked second, after Chile, for batoid landings from 1950 to 2015. Of the twenty-three species of marine batoids that interact with Peruvian fisheries, the most landed taxonomic groups, from 1997 to 2015, were: Myliobatis spp. (i.e., M. chilensis and M. peruvianus; 45% of batoids landings), Mobula spp. (primarily M. mobular, and secondarily M. thurstoni, M. munkiana, M. tarapacana; 28%), Pseudobatos planiceps (6%), and Hypanus dipterurus (6%). Most of these species are landed in northern Peru, where gillnets are the most-used fishing gear to capture them. Batoid landings occurred year-round; yet, for H. dipterurus and P. planiceps landings were highest during the austral summer. Only three management measures exist for batoids fisheries in Peru for three species (i.e., M. birostris, Pristis pristis, Rhinoptera steindachneri) and two taxa (i.e., Mobula and Myliobatis) which are not fully enforced. Batoid research in Peru is limited, with only 25 publications from 1978 to 2022, in which the most studied species are Mobula birostris, M. chilensis and M. peruvianus. This study establishes an information baseline for batoids in Peru that can help guide their management, research, and conservation. &nbsp

Preliminary analysis of the feeding habits of batoids from the genera Mobula and Myliobatis in northern Peru

This study provides baseline information on the feeding habits of five batoid species from the genera Mobula and Myliobatis sampled from the small-scale driftnet fishery in northern Peru. The diets of Mobula mobular, Mobula munkiana and Mobula thurstoni consisted mainly of euphausiids. Dietary niche breadth indicated a pelagic feeding behaviour of a specialist and a trophic level of a secondary predator for both M. mobular and M. munkiana. In contrast, Myliobatis chilensis and Myliobatis peruvianus consumed mostly gastropods and crustaceans. Dietary niche breadth indicated a feeding behaviour of a benthic specialist and a trophic level of a secondary predator for Myliobatis chilensis