| 1. |
- Knief, Ulrich, et al.
(författare)
-
Highly pathogenic avian influenza causes mass mortality in Sandwich Tern Thalasseus sandvicensis breeding colonies across north-western Europe
- 2024
-
Ingår i: Bird conservation international. - : Cambridge University Press. - 0959-2709 .- 1474-0001. ; 34
-
Tidskriftsartikel (refereegranskat)abstract
- In 2022, highly pathogenic avian influenza (HPAI) A(H5N1) virus clade 2.3.4.4b became enzootic and caused mass mortality in Sandwich TernThalasseus sandvicensis and other seabird species across north-western Europe. We present data on the characteristics of the spread of the virus between and within breeding colonies and the number of dead adult Sandwich Terns recorded at breeding sites throughout north-western Europe. Within two months of the first reported mortalities, 20,531 adult Sandwich Terns were found dead, which is >17% of the total north-western European breeding population. This is probably an under-representation of total mortality, as many carcasses are likely to have gone unnoticed and unreported. Within affected colonies, almost all chicks died. After the peak of the outbreak, in a colony established by late breeders, 25.7% of tested adults showed immunity to HPAI subtype H5. Removal of carcasses was associated with lower levels of mortality at affected colonies. More research on the sources and modes of transmission, incubation times, effective containment, and immunity is urgently needed to combat this major threat for colonial seabirds.
|
|
| 2. |
- Liljebäck, Niklas, et al.
(författare)
-
Prevalence of imbedded and ingested shot gun pellets in breeding sea ducks in the Baltic Sea—possible implications for future conservation efforts
- 2023
-
Ingår i: European Journal of Wildlife Research. - 1612-4642. ; 69:4
-
Tidskriftsartikel (refereegranskat)abstract
- Several sea duck species in Europe face dwindling population numbers with following increased conservation focus. Shot gun practices may put extra pressure on populations not only by direct hunting mortality but also crippling and lead poisoning from ingestion of pellets. In this study, we examined three sea duck species breeding in the Swedish Archipelago of the Baltic Sea by x-raying trapped incubating females to detect prevalence of imbedded and ingested shot gun pellets. The study was carried out during the 2021 and 2022 breeding seasons and designed to aid our understanding of the role of physical restraints of putative pellets to breeding performance at our study site. A total of 205 individual females of common eider (n = 113), velvet scoter (n = 57), and red-breasted merganser (n = 35) were x-rayed without finding any imbedded or ingested pellets. For this study, a combination of decreasing hunting pressure, remoteness of study site, improved hunters’ shooting performance along the flyway and depletion of crippling rates due to life-long negative effects of carrying imbedded pellets may explain our finding on non-detection. For common eider, specific interventions to reduce the negative impacts of shotgun practices have been reported successful, and our data suggest a continuing positive trend. Based on our findings, we advise future conservation efforts for the three species, breeding in this part of the flyway, to focus on other factors that may have negative impact on incubating female survival and reproduction.
|
|
