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Since the beginning of the 21st century, electronic monitoring (EM) has emerged as a cost-efficient supplement to existing catch monitoring programmes in fisheries. An EM system consists of various activity sensors and cameras positioned on vessels to remotely record fishing activity and catches. The first objective of this review was to describe the state of play of EM in fisheries worldwide and to present the insights gained on this technology based on 100 EM trials and 12 fully implemented programmes. Despite its advantages, and its global use for monitoring, progresses in implementation in some important fishing regions are slow. Within this context, the second objective was to discuss more specifically the European experiences gained through 16 trials. Findings show that the three major benefits of EM were as follows: (a) cost-efficiency, (b) the potential to provide more representative coverage of the fleet than any observer programme and (c) the enhanced registration of fishing activity and location. Electronic monitoring can incentivize better compliance and discard reduction, but the fishing managers and industry are often reluctant to its uptake. Improved understanding of the fisher's concerns, for example intrusion of privacy, liability and costs, and better exploration of EM benefits, for example increased traceability, sustainability claims and market access, may enhance implementation on a larger scale. In conclusion, EM as a monitoring tool embodies various solid strengths that are not diminished by its weaknesses. Electronic monitoring has the opportunity to be a powerful tool in the future monitoring of fisheries, particularly when integrated within existing monitoring programmes.

Responsible fisheries management requires the consideration of fishing effects on ecosystems including non-target species. Extensive distributional overlap between fisheries and seabirds, and the attractiveness of the catch and fishery waste to foraging birds, leads to fatal interactions between seabirds and fishing gear. In a series of experiments, we have investigated measures for managing trawl processing waste to reduce seabird mortalities. Different fisheries generate different volumes of processing waste, and vessel capacities for holding this waste can vary significantly both within and between trawl fleets. Here, we compare seabird responses to discharging trawl fisheries waste ad hoc, as and when waste became available, with responses to discharging waste after holding periods of 30 min and 2 h. Using abundance as a proxy for the risk of mortality, we show that compared to discharging ad hoc, holding waste for two specified periods prior to discharge significantly reduces vessel attendance by small seabirds, and both small and large seabirds, respectively. Drawing on this study and our past work, we provide best practice guidelines for trawler waste management to reduce seabird mortality due to interactions with trawl warps. If the ideal approach of discharging waste only when fishing gear is out of the water is impossible, then discharging waste rapidly in maximally large batches, as infrequently as possible is recommended. Holding periods of 30 min to 8 h may be required to reduce the abundance of small species of seabirds attending vessels. For large seabirds, holding periods of 2–4 h are required, and 8 h holding periods are still more effective. Discharging waste as it becomes available is not recommended. Mincing processing waste can reduce the attendance of some seabird species at vessels, especially large albatrosses. However, holding waste is preferred, due to relative simplicity in the mechanics of dealing with waste, lower cost, and greater reductions in seabird abundance. Though developed on trawl fisheries, principles of these guidelines are applicable to any fishery discharging waste attractive to seabirds. While holding fisheries waste can minimise seabird captures on trawl warps worldwide, evidence-based management measures are still required to reduce seabird mortalities in trawl nets.

By-catch ofseabirdson trawl-fishing gear has been reported worldwide,and is exacerbated by thedischarge of fisheries waste. We compared the attraction of seabirds to three forms of fishery waste-unprocessed discharge (offal, fishdiscards),hasheddischarge(smallerchunkspassedthroughahasherpump)andcutterpumpdischarge(wastepassed through thehasher and acutterpump to further reduce particlesize)-to identify thedischarge formthat most effectively reduced the risk of seabird by-catch. Seabird responses measured within specified areas astern of the vessel were the abundanceof:largealbatrosses(Diomedeaspp.),smallalbatrossesandgiant-petrels(Thalassarchespp.;SouthernGiant- Petrels, Macronectes giganteus; and Northern Giant-Petrels, M. halli), Cape Petrels (Daption capense) and all other procellariid species. Seabirds on the water were less numerous during cutter pump and hashed discharge relative to unprocessed discharge (except small albatrosses - cutter treatment). Also, in some cases, the total number of birds decreased, relative to unprocessed discharge treatments (but not small and large albatrosses - cutter treatment). Particle sizemaybelessimportantforreducingabundancesthantemporaldischargepatterns,whichaffectedhowbirdstrackedthe discharge stream. Manipulating discharge characteristics can reduce seabird attraction to fishing vessels. However, the risk of by-catch remained lowest when no discharging occurred.

Seabird bycatch in trawl fisheries is driven by the attraction of birds to foraging opportunities, i.e., the discharge of catch processing waste and the contents of trawl nets. The risk of seabird captures increases with seabird abundance and exposure to fishing gear. We investigated (1) how quickly seabirds responded to discharges of trawl catch processing waste and (2) whether decreasing numbers of seabirds attended trawlers during processing waste discharge events as the time interval between these events increased. Waste was retained onboard the vessel for four different holding periods (30 min, 2 h, 4 h, 8 h), one of which was applied each day using a randomised block design. We determined seabird responses to batch discharge events after the prescribed holding periods using the abundance of large (albatrossses and giant petrels Macronectes spp.) and small (all other petrels except cape petrels Daption capense, shearwaters and prions) seabirds in a semi-circle of 40 m radius, centred on the stern of the experimental trawler. Seabird responses reflected the type of discharge released: birds moved from the air to the water, as the amount of food available increased from no discharge, through sump discharge to batch discharge. When discharge occurred, seabird abundance increased faster than could be resolved with the 5 min sampling period. However, abundance decreased more slowly over a 10-15 min period after the discharge event. The number of large seabirds attending the vessel during discharge events decreased significantly when waste was held for 4 h. For small birds, significant decrease occurred after 8 h. Such holding periods emphasise the tenacity of foraging seabirds, although we have not evaluated any long-term habituation to a particular discharge regime. While holding waste for less than 4 h may not reduce seabird attendance during discharge events, holding for shorter intervals can still reduce

The risk of seabird bycatch in trawl fisheries is increased by high numbers of seabirds attending vessels to feed on fish waste discharged. We conducted an experimental test of whether mincing fish waste prior to its discharge from a factory trawler reduced the number of seabirds attending the vessel. The trial was conducted on a mid-water trawler targeting hoki ( Macruronus novaezelandiae ) in New Zealand waters, and the experiment compared three treatments (1) discharging ‘unprocessed’ waste (fish offal and whole discards), (2) mincing all waste to a small particle size before discharge, or, (3) converting all waste to fishmeal and reducing discharge to sump water. The response to the experimental treatments was determined using seabird abundance within a 40 m-radius semi-circular area centred on the vessel stern. Mincing reduced the numbers of large albatrosses ( Diomedea spp.) feeding astern of the vessel, but had no significant effect on other groups of seabirds. In contrast, reducing discharge to sump water resulted in a significant reduction in numbers of all groups of seabirds. In particular, the abundance of the small albatross group (principally Thalassarche spp.), and some smaller procellarids (e.g. sooty shearwater, Puffinus griseus , and white-chinned petrel, Procellaria aequinoctialis ), was reduced to less than five percent of the number that were within the sweep area when unprocessed discharge was released. While mincing significantly reduced the abundance of large albatrosses at the vessel stern, relatively small numbers of these birds attend trawl vessels in New Zealand waters and associated bycatch rates are low. In contrast, reducing the quantity of fish waste discharge by mealing resulted in reduced abundances of a wide range of seabirds at the vessel. Therefore, compared to mincing, we recommend fish waste retention as a more effective management strategy for reducing seabird bycatch.

In a previous study, we reported that deploying small amounts of biogenic oil derived from the livers of school sharks (Galeorhinus galeus) was effective in reducing the numbers of seabirds attending fishing vessels and seabird diving activity in the Hauraki Gulf, New Zealand. This seabird assemblage was numerically dominated by Flesh-footed Shearwaters (Puffinus carneipes) and the globally vulnerable Black Petrel (Procellaria parkinsoni). The results suggested that the oil deterrent operated via an olfactory or chemesthetic mechanism. Here we compare the deterrent effects of shark-liver oil with three other fish oils, in the Flesh-footed Shearwater–Black Petrel assemblage. We also report on trials assessing the deterrent efficacy of shark-liver oil and one other fish oil in an assemblage including four species of albatrosses (Diomedea spp., Thalasarcche spp.), Southern and Northern Giant-Petrels (Macronectes giganteus and M. halli), and Cape Petrels (Daption capense). Shark-liver oil was the most effective deterrent of the four fish oils tested in the Flesh-footed Shearwater–Black Petrel assemblage, but it did not deter albatrosses, giant-petrels or Cape Petrels from attending vessels. Thus, the deterrent was effective only on burrow-nesting seabird species. These results may provide further support for our speculation that the deterrent operates via an olfactory mechanism, while corroborating other work linking life-history characteristics of seabirds to their sensory ecology. We recommend research to investigate the mechanism and active ingredients by which shark-liver oil deters some species of seabirds. We also suggest testing fish oils on White-chinned (Procellaria aequinoctialis) and Grey (Procellaria cinerea) Petrels, and Sooty Shearwaters (Puffinus griseus), as well as in other areas occupied by Flesh-footed Shearwaters, to assess further potential for this natural oil or its ingredients to reduce by-catch of seabird species globally.

Longline fisheries throughout the world have frequent and often fatal interactions with seabirds. We experimentally tested one possible solution to seabird–fisheries interactions that was proposed by a New Zealand longline fisherman. This involved dripping school shark Galeorhinus galeus liver oil on the ocean surface behind fishing vessels. We tested the efficacy of shark liver oil in reducing the numbers of seabirds attending fishing vessels and the number of dives seabirds executed in pursuit of pilchard Sardinops neopilchardus baits. We conducted trials in northern New Zealand where seabird assemblages include the globally vulnerable black petrel Procellaria parkinsoni . Shark liver oil was effective in reducing both seabird numbers and dives on baits, compared to canola oil and seawater control treatments. Comparisons of seabird responses to shark liver oil and vegetable oil suggest that shark liver oil acts as an olfactory or chemesthetic deterrent for seabirds. Further work should include testing the oil with additional seabird species and investigating active ingredients and habituation of seabirds to the oil in order to assess wider opportunities for long-term use of shark liver oil to reduce seabird bycatch.

We compared foraging behavior of Bufflehead (Bucephala albeola Linnaeus) and Common Loon (Gavia immer Brunnich) on eight lakes in harvested and unharvested boreal mixedwood forest in northern Alberta, Canada. For one summer before (1996) and two summers after (1997, 1998) forest harvesting around three of the eight lakes, we recorded the duration of Bufflehead and Common Loon dives. After logging, forested buffer strips 100 m-wide separated cut-blocks from lakes (‘harvested lakes’). ‘Unharvested lakes’ were surrounded by ⩾450 m of undisturbed forest throughout the study. There were no detectable differences in dive duration between harvested and unharvested lakes for Bufflehead or Common Loon. Correlations between environmental variables (water clarity, fish biomass, depth) and the duration of Common Loon dives were not significant. However, the duration of Bufflehead dives differed between lakes, unrelated to forest harvesting. The duration of Buffle-head dives was negatively correlated with wat...

Using satellite tracking, we have followed the migration of birds in Asia for more than 10 years. We have investigated the migration patterns of around 15 species of birds, focusing on, but not limited to, cranes (Gruidae) and storks (Ciconiidae). To relay bird locations, we employed platform transmitter terminals in combination with ARGOS satellites. Location data were then utilized in a variety of applications, from determining migration routes, stopover patterns and wintering sites, through more advanced analyses including using various data overlays to examine habitat use, occupation of nature reserves, differential migration patterns between adults and juvenile birds, and the connectivity and network structure of migration pathways. We have also developed recommendations for spatial improvements to nature reserves. We emphasize the importance of continued empirical research and development of analytical methodologies involving satellite location data in concert with effecting conservation outcomes using satellite-derived data.

We investigated the application of satellite tracking to the conservation of cranes and other waterbirds and the necessity of international cooperation in the conservation of migratory species. Using satellite tracking, we followed 11 White-naped Cranes (Grus vipio) on migration from their breeding grounds in eastern Russia to their wintering grounds in China and Japan. From 1991 to 1993, we captured cranes with the aid of helicopters and attached satellite transmitters (platform transmitter terminals) to captured birds via a harness system. We tracked cranes for 156 days on average, across 2558 km, and obtained an average of 339 locations per crane. Cranes migrated over 8–90 days. During migration, birds spent 1–30 days at 4–12 rest sites. Cranes wintered at two main sites: Poyang Lake, China, and Izumi, Japan. All seven cranes migrating to the Poyang Lake area rested at the Yellow River delta–Bohai Bay, China, and all three traveling to Izumi rested in the Demilitarized Zone on the Korean Peninsula. Other important rest sites were marshes around the Wulagai River, Huainan, Hu-Lun Lake, Linyi, Tangshan, the Three Rivers (Sanjiang) Plain, Tianjin, and the Xar Moron River, all in China, and Lake Khanka–Xinghai at the border of China and Russia. The habitats resting cranes used most frequently were plains, including upland areas, marshes, and rivers. Although nature reserves exist at the two main wintering sites of Poyang Lake and Izumi, rest sites used by cranes were poorly protected. Even when areas used by cranes for resting or wintering were included in nature reserves, reserves were threatened by human encroachment and development. To ensure that cranes can continue to migrate successfully, it is crucial that the establishment of reserves continues at important rest areas and that the areas covered by reserves at wintering sites be extended to include more of the areas utilized by cranes. Also, development and human disturbance should be minimized in reserve areas. Because long-distance migrant birds, including cranes, range over such large areas, conservation of these organisms and their habitats necessitates multinational communication and cooperation. Resumen: Investigamos la aplicacion del rastreo por satelite a la conservacion de grullas y otras aves acuaticas y la necesidad de cooperacion internacional en la conservacion de especies migratorias. Utilizando el rastreo por satelite, seguimos la migracion de 11 grullas de nuca blanca (Grus vipio), desde sus areas de reproduccion en Rusia oriental hasta su area de hibernacion en China y Japon. De 1991 a 1993 capturamos grullas con la ayuda de helicopteros y les colocamos transmisores de satelite (terminales de transmisor de plataforma) mediante un sistema de arnes. Rastreamos a las grullas por 156 dias en promedio, a lo largo de 2558 km, y obtuvimos un promedio de 339 localidades por grulla. Las grullas migraron por 8-90 dias. Durante la migracion, las aves estuvieron de 1-30 dias en 4-12 sitios de descanso. Las grullas invernaron en dos sitios principales: Lago Poyang, China e Izumi, Japon. Las siete grullas que migraron al area del Lago Payong descansaron en el delta del Rio Amarillo/Bahia Bohai, China, y las tres que viajaron a Izumi descansaron en la Zona Desmilitarizada en la Peninsula Coreana. Otros sitios de descanso importantes fueron humedales alrededor del rio Wulagi, Huainan, Lago Hu-Lun, Linyi, Tangshan, la Llanura Tres Rios (Sanjiang), Tianjin y el Rio Xar Moon, todos en China, y el Lago Khanka/Xinghai en la frontera entre China y Rusia. Los habitats utilizados mas frecuentemente para descanso fueron llanuras, incluyendo areas elevadas, cienegas y rios. Aunque existen reservas naturales en el Lago Poyang e Izumi, los dos principales sitios de hibernacion, los sitios utilizados para descanso estan mal protegidos. Aun cuando las areas utilizadas por las grullas para descanso estuvieran en reservas naturales, las reservas estaban amenazadas por invasion y desarrollo humano. Para asegurar que las grullas puedan continuar migrando exitosamente, es crucial que continue el establecimiento de reservas en areas de descanso importantes y que se extiendan las areas cubiertas por reservas en sitios de hibernacion para incluir mas de las areas utilizadas por grullas. Tambien, se debe minimizar el desarrollo y la perturbacion humana en las areas de reserva. Debido a que las aves migratorias de larga distancia, incluyendo grullas, se distribuyen en areas muy extensas, la conservacion de estos organismos y sus habitats requiere de comunicacion y cooperacion multinacionales.

Translocation is a commonly used tool in conservation management. However, because post-release monitoring has been infrequent in the past, reasons for the outcomes of translocations have often been unknown. Here, I review the reintroduction biology (including dispersal patterns, social organisation, survival, habitat use and foraging patterns) of a population of 26 South Island Saddlebacks (Philesturnus carunculatus carunculatus), on Motuara Island, New Zealand. After release on Motuara Island, South Island Saddlebacks dispersed widely through forest areas. During their first post-release breeding season, saddlebacks established territories of 1.9 ha-8.8 ha (X¯=4.21 ha, SD=2.42) in size, and territorial confrontations were very rare. Saddlebacks bearing both adult and subadult plumage held territories and attempted to breed, and successful breeding produced approximately 10 fledglings. Saddlebacks foraged on a variety of plant species, dead wood and the ground. Except for five-finger (Pseudopanax arboreus), a preferred foraging substrate, birds foraged in all plant material in proportion to its availability. Saddlebacks preferred to forage in the lower levels of the forest. Although vegetation composition differed significantly between territories, all territories contained forest areas, and birds appeared to prefer foraging in larger sized trees. Large territory sizes, breeding attempts by young birds and rarity of territorial confrontations are most likely products of low population density. As density increases, birds are expected to occupy smaller territories, forage more efficiently within these smaller areas, start breeding at older ages, and possibly colonise scrub habitats. The translocated group sustained no more than 50% mortality at 8-10 months after release. In the past, translocations of 15–59 South Island Saddlebacks have been successful, suggesting that the relatively small founder group does not threaten the success of the transfer to Motuara Island. Saddlebacks are flexible in their habitat use, appear to readily adapt to ‘new’ environments and have high reproductive potential, increasing the likelihood of success of translocations of this species.

Translocations have been widely used to conserve threatened fauna worldwide, and although the benefits of monitoring newly translocated animals are widely recognised, post-release monitoring seldom occurs. This paper reports the dispersal patterns, social organisation and survival of a newly translocated population of 26 South Island saddlebacks (Philesturnus carunculatus carunculatus), on Motuara Island, New Zealand. South Island saddlebacks dispersed widely through forest on Motuara Island after release and 8–10 months after release, territory sizes ranged from 1.9–8.8 ha ( x =4.21 ha, s=2.42). Saddlebacks in both subadult and adult plumage attempted to breed in the first breeding season after release and an estimated 10 fledglings were produced. Maximum mortality of the translocated group was 50% 8–10 months after release. Translocations of 15–59 South Island saddlebacks have been successful in the past, suggesting the success of the transfer to Motuara Island is not jeopardised by the relatively small size of the founder group. Saddlebacks appear relatively flexible in habitat requirements and are capable of high reproductive output, enhancing the success of translocations of this species.