Literature type: Scientific
Journal: Bird Conservation International
Volume: 33 , Pages: e42, 1–8
DOI: 10.1017/S0959270922000478
Language: English
Full reference: Kruckenberg, H., Moonen S., Kölzsch, A., Liljebäck, N. & Müskens, GJDM. 2022. Migration routes and stepping stones along the western flyway of Lesser White-fronted Geese (Anser erythropus). Bird Conservation International 33: e42, 1–8 https://www.dx.doi.org/10.1017/S0959270922000478
Keywords: reintroduction, Sweden, migration routes, tracking, Brownian bridge, dBBMM,
Abstract:
In 2015 and 2016 four Lesser White-fronted Geese (Anser erythropus), a globally threatened species, were caught and tagged during spring migration representing nearly 10% of the entire Swedish breeding population at the time. Two of the birds were followed over more than one season. Tracking data revealed an unexpected wide network of migration corridors and staging sites. Autumn and spring migration differed by stepping-stone sites and migration speed. So far unknown key stopover sites were discovered in Denmark, northern Germany, and Sweden. By using dynamic Brownian bridge movement models, the potential areas that Lesser Whitefronted Geese used during migration are described and conservation implications spotlighted. This study provides another important piece of the puzzle describing the migration of Lesser White-fronted Geese in Western Europe.
Literature type: Scientific
Journal: Ornis svecica
Volume: 31 , Pages: 125–138
Language: English
Download:Full reference: Liljebäck, N., Koffijberg, K., Kowallik, C., Månsson, J. & Andersson, Å. 2021. Use of foster parents in species conservation may cause conflicting objectives: Hybridization between Lesser White-fronted Goose Anser erythropus and Barnacle Goose Branta leucopsis. Ornis svecica 31: 125–138 https://www.dx.doi.org/10.34080/OS.V31.22430
Keywords: reintroduction, foster parents, Sweden, hybridization
Abstract:
Following the use of Barnacle Geese Branta leucopsis as foster parents in a conservation program for the endangered Lesser White-fronted Goose Anser erythropus in Sweden 1981–1999, mixed breeding pairs of the two species were established in the wild. We find indications that this was related to shared moulting habits of the two species in the Bothnian Sea during late 1990s. Starting in 2003, five mixed pairs produced at least 49 free-flying hybrid offspring until 2013, when the last breeding was confirmed. Reported numbers of hybrids did not increase in parallel to the production of young hybrids over time. After 2013, the number of hybrids started to decrease in Sweden and the Netherlands. Lower numbers of hybrids than expected can partly be explained by management actions taken, but may also be associated with low survival due to genetic outbreeding. Mixed pairs and their offspring entirely adopted the migratory habits of Barnacle Geese, overlapping very little with sites used by Lesser White-fronted Geese. We find no evidence that the hybrids ever posed a serious threat to Lesser White-fronted Geese breeding in Fennoscandia.
Literature type: Scientific
Journal: Scientific Reports
Volume: 10 , Pages: 18347
DOI: s41598-020-75315-y
Language: English
Download:Full reference: Díez‑del‑Molino, D., von Seth, J., Gyllenstrand, N., Widemo, F., Liljebäck, N., Svensson, M., Sjögren‑Gulve, P. & Dalén, L. 2020. Population genomics reveals lack of greater white‑fronted introgression into the Swedish lesser white‑fronted goose. Scientific Reports 10: 18347 https://www.dx.doi.org/s41598-020-75315-y
Keywords: reintroduction, farming, introgression, hybridization
Abstract:
Interspecific introgression is considered a potential threat to endangered taxa. One example where this has had a major impact on conservation policy is the lesser white-fronted goose (LWfG). After a dramatic decline in Sweden, captive breeding birds were released between 1981–1999 with the aim to reinforce the population. However, the detection of greater white-fronted goose (GWfG) mitochondrial DNA in the LWfG breeding stock led to the release program being dismantled, even though the presence of GWfG introgression in the actual wild Swedish LWfG population was never documented. To examine this, we sequenced the complete genomes of 21 LWfG birds from the Swedish, Russian and Norwegian populations, and compared these with genomes from other goose species, including the GWfG. We found no evidence of interspecific introgression into the wild Swedish LWfG population in either nuclear genomic or mitochondrial data. Moreover, Swedish LWfG birds are genetically distinct from the Russian and Norwegian populations and display comparatively low genomic diversity and high levels of inbreeding. Our findings highlight the utility of genomic approaches in providing scientific evidence that can help improve conservation management as well as policies for breeding and reinforcement programmes.
Literature type: Report
Language: English
Download:Full reference: Schekkerman, H. & Koffijberg, K. 2019. Annual survival in the Swedish Lesser White-fronted Geese. , Sovon-report 2019/63, Sovon Vogelonderzoek Nederland, Nijmegen. 22 pp.
Keywords: reintroduction, farming, releases, survival, Sweden
Abstract:
This report presents the first effort to estimate annual survival rates in the LWfG from the Swedish breeding population. It is among the first studies at all to quantify annual survival probabilities in this highly threatened species. An extensive dataset with live resightings was used as input in a mark-recapture survival analyses in MARK. At present, resighting probabilities of the marked birds are very high, i.e. >95%, thus reflecting nearly the entire ringed population. This is made possible by a large number of volunteer ring readers and dedicated effort of the project to facilitate ring reading at key staging sites (see Figure 1). Figure 4 summarises the survival rates described in chapter 3. The main conclusions that can be drawn from the analyses are: 1) During the first project phase (period 1, releases until 1999) there was an overall increase in annual survival probabilities in all age-classes in the course of the project, i.e. between 1984-2003. Survival was lowest in birds that had been released as yearlings, without any parental care, followed by first-year survival in birds that had been released as juveniles with Barnacle Goose as forster parents. Remarkably, survival was slightly higher in the 2nd year after release for birds released as juveniles than in adult birds (3 years and older, birds released as juveniles and yearlings combined); 2) During the second project phase (period 2, after 2010) there was no trend in survival rates over time (but note that this period spans just five years). Birds released as yearlings had rather similar (low) survival probabilities as those in the first project phase. However, first-year survival in birds released as juveniles was lower (and now comparable with birds released as yearlings) than in the first project phase, likely because juveniles were now released without parental care. Again, survival in the 2nd year after release for birds released as juvenile was somewhat higher than adult survival. Adult survival in the second period was lower than in the first period, but also subject to some variation (note standard error). Again note that the period for which this could be calculated is rather short, as only data from 2012-2017 were taken into account.
Literature type: Report
Language: Swedish In Swedish with English summary.
Download:Full reference: Willebrand, T. & Willebrand, S. 2018. Utvärdering av Åtgärdsprogrammet för fjällgås 2011–2017. [Evaluation of the 2011–2017 Action Program for the Lesser White-fronted Goose (Anser erythropus).] , Naturvårdsverket Rapport 6836. 26. pp
Keywords: captive breeding, reintroduction, red fox culling, monitoring, Sweden
Abstract:
This report is an external evaluation of the current Swedish Action Plan for the Lesser White-Fronted Goose (2011-2015, extended until 2017) and parts of the Lesser White-Fronted Goose Project, commissioned by the Swedish Environmental Protection Agency (SEPA). The evaluation has come to the following conclusions: 1. The Lesser White-fronted Goose in Sweden is critically endangered and immigration from other populations, like the small Norwegian population, is not very probable. To secure the species from becoming extinct in in Sweden, larger resources are required than what is currently available in the system for action plans at SEPA. 2. An increased focus on breeding areas is recommended to obtain more data on predator activity, human disturbance and recruitment of released birds from the breeding program. 3. An increased control of the red fox (Vulpes vulpes) population in the breeding area during late winter, and an evaluation of the optimal ratio of released to wild birds in the population, are two highly prioritized actions. 4. Establishing a systematic monitoring program including quality control will make estimates on population development more reliable. 5. Potential breeding areas, with special emphasize on the extent of grazing fields, should be surveyed in the proximity of the present breeding area to estimate the possibility of natural expansion into new areas. 6. The captive breeding and release is well organized and of high quality. (However, as stressed above, an estimate of the optimal numbers of released birds into the wild should be evaluated.)
Literature type: Report
DOI: 10.13140/RG.2.2.31858.30404
Language: English
Download:Full reference: Aarvak, T., Øien, I.J. & Shimmings, P. 2016. A critical review of Lesser White-fronted Goose release projects. , NOF-report 2016-6. 218 pp.
Keywords: release project, reintroduction, translocation, illegal, genetic, distribution, population, court case, hybrid, barnacle goose, carrier species
Literature type: Thesis
Language: English
Full reference: Mandila, J.M. 2015. Problems of translocation: case study Lesser White-fronted Goose. , B.Sc. Thesis. Faculty of Environment and Natural Resources, Freiburg, Germany.
Keywords: reintroduction, evaluation, translocation, thesis, Germany, Sweden
Abstract:
In order to prevent extinction of the endangered Fennoscandian Lesser White-fronted Goose (LWfG) population, several translocation attempts have been conducted since 1981. Reintroductions prior to 2010 were based on captive birds. By altering the species migration route, the birds were led from former breeding grounds of the Fennoscandian population to safer wintering grounds in Western Europe. The subsequent detection of introgression from other goose genes among the source population led to further releases being put on hold. However, hybridization may be a natural phenomena among LWfG, although research supporting such a view is scarce and the data used questionable, probably relying on samples from escapees. Furthermore, reintroduction by means of using a non traditional route has been criticised due to the change in habitat selection and feeding behaviour of the released population. More recently, releases have been carried out with pure bred LWfG using the traditional route to Western Europe. Although this supports the view that the migration route used is an earlier traditional one which got lost as a result of the decline in the Fennoscandian population, analysis of the supporting data shows that the evidence is too scarce to make such an assumption. Since reintroduction is threatening the wild LWfG genetically and ecologically due to the adoption of genetic traits and behaviour caused by inter-breeding with the released population, the restricted resources of suitable birds should be kept for possible future supplementation of the Fennoscandian population in accordance with the IUCN Guidelines. Furthermore, in order to maintain the wild population and lead to its recovery to a favourable conservation status, efforts should concentrate on the reduction of threats along the traditional migration route and the restoration of its natural habitats.
Literature type: Report
Language: English
Download:Full reference: Koffijberg, K. & van Winden, E. 2013. Lesser White-fronted Geese in The Netherlands: a review of trends, phenology, distribtuion patterns and origin. , Sovon-rapport 2013/48. Sovon Vogelonderzoek Nederland, Nijmegen.
Keywords: Reintroduction, wintering, The Netherlands, population trend, occurrence
Literature type: Action Plan
Language: Swedish (In Swedish with English summary)
Download:Full reference: Naturvårdsverket 2011. Åtgärdsprogram för fjällgås 2011–2015 (Anser erythropus) [Action plan for the Lesser White-fronted Goose 2011-2015.] , Rapport 6434, april 2011.
Keywords: Action Plan, Sweden, reintroduction
Literature type: Report
Language: English
Download:Full reference: Marchant, J.H. & Musgrove, A.J. 2011. Review of European flyways of the Lesser White-fronted Goose Anser erythropus. , Research Report 595. British Trust for Ornithology, Thetford.
Keywords: reintroduction
Number of results: 47