Seabird Bycatch: Trends, Roadblocks, and Solutions

Conservation Biology, 1999

Marine Technology Society Journal, 1999

Biological Conservation, 2009

Bird mortality in fishing gear is a global conservation issue and it is recognised that bycatch in industrial longline and trawl fisheries threatens several seabird species. Little is known however about the effects of bycatch in small-scale gillnet fisheries on bird populations. Here we review 30 studies reporting bird bycatch in coastal gillnet fisheries in the Baltic Sea and the North Sea region in order to assess the magnitude of this problem and potential effects on bird populations. All species of diving birds that occur in the study region, including divers (loons), grebes, sea ducks, diving ducks, auks and cormorants, have been reported as dying in fishing nets. The cumulative bycatch estimate extracted from several localized studies providing such information, suggests that about 90,000 birds die in fishing nets annually, a number that is almost certainly a substantial underestimate. We conclude that it is likely that between 100,000 and 200,000 waterbirds are killed per year. Geographic and temporal patterns of bycatch generally matched species distribution and periods of presence. Also, bycatch rates varied depending on species' foraging technique and were influenced by net parameters and fishing depth. To evaluate effects of additive mortality on bird populations, we applied the Potential Biological Removal (PBR) concept to three species with the most extensive bycatch information. Agreeing with PBR assumptions we conclude that bycatch is a matter of concern for at least two of the three assessed species. We suggest that bycatch research in Europe and beyond should aim at unification of principles for bycatch assessment, setting new standards for the monitoring of waterbird populations so that vital rates and mortality data are recorded, and implementing quantifiable criteria for evaluating effects of fisheries bycatch. ut.ee (M. Vetemaa), [email protected] (B. Schirmeister), [email protected] (A. Stipniece), [email protected] (M. Dagys), [email protected] (M. van Eerden), [email protected] (S. Garthe).

Fish and Fisheries, 2005

Mortality in longline fisheries is a critical global threat to most albatross and large petrel species. Here we identify key principles and approaches to identify and achieve broad use of effective seabird by-catch avoidance methods. Despite the availability of highly effective and cost-saving seabird avoidance methods, few longline fleets employ them. Given the political context and capacity of management authorities of the majority of longline fisheries, it is critical to identify seabird avoidance strategies that are not only highly effective, but are also economically viable and commercially practical. Adoption of an international performance standard for longline baited hook-sink rate, and prescribing minimum gear weighting designs that meet this standard that are achievable by all longline fisheries, would be an important step forward towards resolving low use of seabird avoidance methods by vessels, including those in illegal, unregulated and unreported fisheries. Due to differences between fleets, no single seabird avoidance measure is likely to be effective and practical in all longline fisheries. Therefore, testing of seabird avoidance methods in individual fleets is needed to determine efficacy and economic viability. Longline fishers should directly participate in these trials as they have a large repository of knowledge and skills to effectively develop and improve seabird by-catch avoidance techniques, and this provides industry with a sense of ownership for uptake of effective by-catch reduction methods. Establishing protected areas containing seabird colonies and adjacent waters within a nation's EEZ can be an expedient method to address seabird by-catch. However, establishing high seas marine protected areas to restrict longline fishing in seabird foraging areas, which would require extensive and dynamic boundaries and large buffer zones, may not be a viable short-term solution because of the extensive time anticipated to resolve legal complications with international treaties, to achieve international consensus and political will, and to acquire requisite extensive resources for surveillance and enforcement. Analysis of results of research on seabird avoidance methods reveals that the most reliable comparisons of the efficacy of alternative strategies are from comparing the effectiveness of methods tested in a single experiment. Benefits from standardizing the reporting of seabird by-catch rates to account for seabird abundance are described. To provide the most precise inputs for seabird population models, estimates of seabird mortality in longline fisheries should account for seabird falloff from hooks before hauling, delayed mortality of seabirds caught but freed from gear, and mortality caused by hooks discarded in offal. A global problem 36 North Pacific 37 Longline mortality effect on North Pacific albatross populations 38 Loss of caught birds before haul 39 Lessons from results from research on seabird avoidance methods: case study from North Pacific pelagic longline fisheries 39 Fishery-specific solutions 41 Industry direct involvement in research 42 Standardizing reporting seabird by-catch rates 42 Methods for observer program data collection on seabird by-catch 43 Economic viability, practicality and enforceability 43 International initiatives and need for global performance standards to address IUU fishing 44 Marine protected areas, area and seasonal closures 44 Conclusions 45 Acknowledgements 46 References 46

Ecological Applications, 2003

Pelagic longline fisheries worldwide incidentally take long-lived seabird species. This mortality has led to fisheries restrictions to protect seabirds at risk, including Wandering (Diomedea exulans) and Amsterdam Albatross (D. amsterdamensis) in the South Pacific and Spectacled Petrel (Procellaria conspicillata) in the South Atlantic. Because pelagic longline fisheries involve multinational fleets operating in vast ocean regions, assessing total bycatch levels for a seabird is challenging. Here we present a case study of quantifying bycatch from a basin-wide pelagic longline fishery and assessing the populationlevel impact on a vulnerable seabird, the Black-footed Albatross (Phoebastria nigripes) in the central North Pacific. We develop an assessment method that uses observer data to estimate bycatch for one fleet and then uses scenario analysis to estimate bycatch for remaining fleets. Our method generates a bounded estimate of bycatch within an ocean region, ranging from the worst-case to the best-case bycatch scenario. We find that Blackfooted Albatross mortality across all fleets in the central North Pacific may total as much as 10 000 individuals/yr. At this level of mortality, population declines are likely. However, even at the best-case bycatch estimate (5200 individuals/yr), population declines may occur over the next three generations (60 years). Although this analysis requires extensive estimation and extrapolation from existing data, it is critical to provide fisheries managers with bounded estimates of likely population-level effects of current fishing activity.

2001

Marine …, 2009

In most of the world's coastal fisheries, bycatch of marine birds is rarely monitored, and thus the impact on populations is poorly known. We used marine bird strandings to assess the impact of entanglement in Pacific Northwest coastal net salmon fisheries. We compared the magnitude and species composition of fisheries-associated strandings (FAS) to baseline data collected at beaches monitored by citizenscience programs in Washington State and British Columbia, and to seabirds salvaged from gillnets during observer programs. Carcass encounter rates were 16.4 carcasses/km [95% confidence interval (CI): 11.2 to 21.7] for FAS and 1.00 carcasses/km (95% CI: 0.87 to 1.14) for baseline data. Declines in fisheries effort were associated with decreasing FAS, although declines in at-sea seabird abundance may also be at play. Common Murres Uria aalge comprised most of the carcasses in both the FAS (86%) and bycatch studies (71%). Although the total count of murre FAS represented a small fraction (1.3%-6.6%) of baseline mortality accumulated for the Salish Sea over the same period, murre FAS added 0.2%-2.9% to annual mortality rates. Considering the effects of other natural and anthropogenic mortality agents on murres in the region, this species might benefit from further protection. Given the complexity of salmon fisheries management and the ubiquitous distribution of seabirds in the Salish Sea, we recommend the comprehensive adoption of gillnet gear modification to reduce seabird bycatch, a solution that may prove to be beneficial for the vitality of seabird populations and of the fishing industry.

Biological Conservation, 2017

Seabirds, as foragers in marine waters for at least part of their lifecycle, encounter the global fishing fleet in search of marine resources. While fishing gear is designed to catch fish and invertebrates, it also catches unintended species, including seabirds. We reviewed bycatch incidence for 378 marine and coastal bird species in 18 different gear types, and found that 60% (228 species) have been recorded interacting with at least one type of fishing gear. At least one species from each of the taxonomic groups analyzed (generally at the family level) has been documented interacting with fishing gear. With respect to two measures of degree of interaction, four families have a high degree of documented interaction: Gaviidae (loons or divers), Podicipedidae (grebes), Diomedeidae (albatrosses) and Sulidae (boobies and gannets). Set and drift gillnets (among the most studied gear types), have the greatest number of documented species interactions: 92 and 88 species, respectively. Hook gear (longlines and handlines) have documented interactions with 127 species. Together these four gear types have documented bycatch of 193 species. The waters of the Arctic, the Caribbean, the Guinea and Canary Currents in the Atlantic, the Indian Ocean and Asia have been poorly studied. Particular gear types, including industriallydeployed seines, and the artisanal fisheries sector also constitute significant gaps in our knowledge of seabird bycatch patterns worldwide.

Scientific Reports, 2016

Fisheries provide an abundant and predictable food source for many pelagic seabirds through discards, but also pose a major threat to them through bycatch, threatening their populations worldwide. The reform of the European Common Fisheries Policy (CFP), which intends to ban discards through the landing obligation of all catches, may force seabirds to seek alternative food sources, such as baited hooks from longlines, increasing bycatch rates. To test this hypothesis we performed a combined analysis of seabird-fishery interactions using as a model Scopoli's shearwaters Calonectris diomedea in the Mediterranean. Tracking data showed that the probability of shearwaters attending longliners increased exponentially with a decreasing density of trawlers. On-board observations and mortality events corroborated this result: the probability of birds attending longliners increased 4% per each trawler leaving the longliner proximity and bird mortality increased tenfold when trawlers were not operating. Therefore, the implementation of the landing obligation in EU waters will likely cause a substantial increase in bycatch rates in longliners, at least in the short-term, due to birds switching from trawlers to longliners. Thus the implementation of the landing obligation must be carefully monitored and counterbalanced with an urgent implementation of bycatch mitigation measures in the longline fleet. Effects of fishing on marine megafauna are widespread and diverse, mainly due to overfishing, production of discards and bycatch 1-3. Bycatch, the incidental capture of non-target species, is of particular concern for long-lived species with low reproductive rates and delayed sexual maturity, such as seabirds 1. Baited hooks offer the opportunity for an easy meal, yet these entail a very high risk of birds being hooked and subsequently drowned. A recent global review estimated seabird bycatch by longlines in 160,000-320,000 birds per year 4. In fact, for some species, the current rates of bycatch are unsustainable for their long-term viability 5-8. On the other hand, fishery discards may also have profound impacts on the breeding biology, distribution and population dynamics of seabirds, by making available demersal and benthonic species otherwise naturally inaccessible 9-11. Worldwide discards are estimated to be 8% of the total catch (i.e. around 7,000,000 tonnes discarded annually 2). Ultimately, discards seem to be responsible for the increases in population sizes of several scavenging species over the last decades, such as large gulls 9,12. Seabird-fishery interactions are of particular concern in the Mediterranean 13 ; an enclosed and low-productive sea with a high degree of endemism 14. Four seabird species are endemic to the basin and commonly caught by fishing gear, particularly in longlines: the Audouin's gull Larus audouinii, and the Scopoli's Calonectris diomedea, Yelkouan Puffinus yelkouan and Balearic shearwaters Puffinus mauretanicus 15,16. Among these, the Yelkouan and Balearic shearwaters are globally threatened (Vulnerable and Critically Endangered, respectively 17). According to conservative estimates, at least 5,000 birds could be killed annually in the region 18. In particular, the bycatch of Scopoli's shearwaters represents over 50% of all birds caught in longlines in some areas of the Western Mediterranean, which would imply that 4-6% of the local population breeding in the Balearic Islands is killed every year 4,19,20. For these species, bycatch by other gears appears to be far less relevant in the region 15,16 .

Anthropological Quarterly, 2018

This article explores the links between informal moneylending and aspects of sociality and morality. It documents the moral reasoning and strategizing of two female moneylenders who operate in the radically destabilized context of post-Soviet Kyrgyzstan. By analyzing these women's lending practices and the way they talk about their experiences, we are able to document in some detail the constitutive intertwinement of morality, sociality, and formality in the workings of credit and debt, and demonstrate how questionable behavior is transformed into moral practice. This in turn highlights important features of the post-Soviet capitalist frontier.