Changes in fisheries discard rates and seabird communities

@article{Votier2004ChangesIF,
  title={Changes in fisheries discard rates and seabird communities},
  author={Stephen C. Votier and R. W. Furness and Stuart Bearhop and Jonathan E. Crane and R. W. G. Caldow and Paulo Catry and K. L. Ensor and Keith C. Hamer and Anne V. Hudson and Ellen Kalmbach and Nicholas I. Klomp and Simone Pfeiffer and Richard A. Phillips and Isabel Prieto and David R Thompson},
  journal={Nature},
  year={2004},
  volume={427},
  pages={727-730}
}
It is clear that discards from commercial fisheries are a key food resource for many seabird species around the world. But predicting the response of seabird communities to changes in discard rates is problematic and requires historical data to elucidate the confounding effects of other, more ‘natural’ ecological processes. In the North Sea, declining stocks, changes in technical measures, changes in population structure and the establishment of a recovery programme for cod (Gadus morhua) will… 
Effects of Fisheries on Seabird Community Ecology
TLDR
In this review, seabirds were separated into three functional groups based on their primary foraging strategy when they are likely to interact with fishing vessels: kleptoparasites, scavengers, and pursuit-divers.
Potential consequences of discard reform for seabird communities
TLDR
The potential for both negative and positive impacts of discard reforms for seabirds are considered, with particular focus on the EU, and recommendations for ongoing research and conservation are proposed.
Influence of management practices and of scavenging seabirds on availability of fisheries discards to benthic scavengers
TLDR
Amounts and composition of fishery discards and offal reaching benthic scavenging communities are clearly very strongly influenced by the intense but selective consumption by seabirds, and this alteration will depend strongly on details of the fishery management regulations and customs, such as whether or not waste is macerated.
Temporal and spatial variation in the diet of a marine top predator—links with commercial fisheries
TLDR
The results indicate that great skuas rely heavily on fishery discards and are also sensitive to spatial and temporal changes in fisheries activity.
Relative abundance and distribution of fisheries influence risk of seabird bycatch
TLDR
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 and the implementation of bycatch mitigation measures in the longline fleet must be carefully monitored and counterbalanced.
Seabird-trawling interactions: factors affecting species-specific to regional community utilisation of fisheries waste
TLDR
Seabird-trawling interactions throughout the annual cycle in a poorly studied ecosystem in the Mediterranean, the Balearic archipelago, are studied on a both species-specific and a community level, showing a significant influence of season on shaping seabird’s trawling attendance patterns.
Favorites and leftovers on the menu of scavenging seabirds: modelling spatiotemporal variation in discard consumption
TLDR
To quantify both portions of discards temporally as well as spatially, a modelling framework was applied to a case study in the Bay of Biscay, where a wide variation in discard consumption was observed across seabird foraging guilds, discard types, periods, and locations.
Do individual seabirds specialize in fisheries' waste? The case of black‐browed albatrosses foraging over the Patagonian Shelf
TLDR
It is suggested that scavenging albatrosses, a group particularly threatened by fisheries activity, do not specialize in discards, and any management actions leading to a reduction of discards will be beneficial, decreasing the numbers of birds behind vessels and consequently the likelihood of incidental mortality.
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 49 REFERENCES
Impacts of fisheries on seabird communities
TLDR
While piscivorous fish stocks remain low, sandeel fishery and seabirds appear to be able to coexist, however, if piscive fish stocks recover in the North Sea, reduced availability of sandeels to seab birds may affect certain species.
Management implications of interactions between fisheries and sandeel-dependent seabirds and seals in the North Sea
TLDR
Overall, there appears to have been a reduction in mortality during the last 30 years, which implies that seabird and seal food supply in terms of sandeel may be strongly dependent on decisions regarding management of stocks of mackerel and gadoids.
Fish discarded from Scottish demersal vessels: Estimators of total discards and annual estimates for targeted gadoids
The main objective of discard sampling programmes is to estimate annual total discards of fish species whose stocks are routinely assessed from catch data. The Scottish discard programme is based on
The impact of great skua predation on seabird populations at St Kilda: a bioenergetics model
TLDR
Estimation of the total mass of different prey consumed at St Kilda and the potential impact of this predation on other seabird populations suggests that great skuas may have a considerable impact on the internationally important populations of some seabirds at StKilda.
Annual Variation in Great Skua Diets: The Importance of Commercial Fisheries and Predation on Seabirds Revealed by Combining Dietary Analyses
TLDR
This study combines conventional dietary assessment with stable isotope techniques to describe Great Skua (Stercorarius skua) diet, and finds that a combined approach is likely to become increasingly useful in elucidating the diets of polyphagous birds.
Effects of winter fishery activities on resting numbers, food and body condition of large gulls Larus argentatus and L. marinus in the south-eastern North Sea
TLDR
The results show for the first time a strong influence of discard availability on numbers and body condition of large gulls wintering in the south-eastern North Sea.
Effects of trawler discard availability on egg laying and breeding success in the lesser black-backed gull Larus fuscus in the western Mediterranean
  • D. Oro
  • Environmental Science, Biology
  • 1996
TLDR
A comparison between 2 breeding seasons of the lesser black-backed gull has allowed an assessment of the effects of discard availability on its egg laying and population dynamics of the species is probably affected by changes in trawler discard availab~lity.
INFLUENCES OF FOOD AVAILABILITY AND PREDATION ON SURVIVAL OF KITTIWAKES
Life history theory predicts a trade-off between current reproduction and survival to maximize fitness. In long-lived seabirds, one might expect adults not to jeop- ardize survival by excessive
The effects of changes in food availability on the breeding ecology of great skuas Catharacta skua in Shetland
TLDR
Changes in the age structure of the breeding population and the absence in 1989 of 28% of adults colour-ringed during incubation in 1988 suggest an increase in the rate of egress since the 1970s, which probably represents an increased in the long-term costs of reproduction to adults at this colony.
Non-breeders as a buffer against environmental stress : declines in numbers of great skuas on Foula, Shetland, and prediction of future recruitment
TLDR
This study supports the suggestion of Porter & Coulson (1987) that numbers of non-breeders at seabird colonies may provide an early and sensitive indication of environmental changes having adverse effects on the population, since non-Breeders act as a buffer to such stress.
...
1
2
3
4
5
...