The fourth subpopulation has been created by the release of captive-bred birds within the former range of the Fennoscandian population in Sweden and by the establishment of a human-modified flyway. The Fennoscandian’ and Western main populations underwent significant declines during the twentieth century and continue to decrease, due primarily to hunting pressure and habitat loss along migration routes and in the wintering areas. The reintroduced population appears to be increasing slowly, but views differ markedly on the ethical and scientific merits of the conservation measures applied for this species and their potential implications (e.g. hybridisation risk with other species).
Threats
There is strong evidence that the most important factors driving the continued decline in numbers and fragmentation of range of the Lesser White-fronted Goose (both the Fennoscandian and Western main subpopulations) are those that cause high mortality among fully grown birds. These factors operate primarily on the staging and wintering grounds, given that studies in the breeding range have failed to detect any adverse impacts that are of significant magnitude to explain the population crash. Although the species is legally protected,
on paper at least, across virtually its entire range, hunting is considered to be the primary cause of mortality and the single most important threat that this Action Plan has to tackle. The loss and degradation of suitable habitat is currently considered to be an important but secondary threat to survival of full-grown birds. However, its significance as a likely driver for the historical declines and range changes during the 20th century should not be underestimated.
Focus and content of the Action Plan (see Chapter 5)
Action Plan Goal
To restore the Lesser White-fronted Goose to a favourable conservation status within the AEWA Agreement Area.
Action Plan Purpose
To stop and reverse the current population decline and range contraction.
Results required for delivering the Purpose and Goal
Result 1: Mortality rates are reduced
Result 2: Further habitat loss and degradation is prevented
Result 3: Reproductive success is maximised
Result 4: No introgression of DNA from other goose species into the wild population occurs as a result of further releases and DNA introgression from already released birds from captive breeding programmes is minimised
Result 5: Key knowledge gaps filled
Result 6: International cooperation maximised
For each Result, Objectively Verifiable Indicators, Means of Verification, Priority and Timescale are identified, in addition to the specific
activities needed to achieve the desired Result (see Chapter 6).
Principles of Implementation
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An International Lesser White-fronted Goose Working Group shall be established, consisting of governmental representatives of all Range States. The governmental representatives shall be free to bring in their own experts and to call on their support as required. The Working Group shall be chaired by the AEWA Secretariat (subject to additional, dedicated human and financial resources being made available to the Secretariat) and will operate in accordance with Terms of Reference to be developed by the AEWA Secretariat, approved by the Range States and endorsed by the AEWA Technical Committee.
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The main priority for the conservation of the Lesser White-fronted Goose is the maintenance of the wild populations breeding in Fennoscandia and Russia.
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The efficiency of conservation measures is to be assessed by the International Lesser White-fronted Goose Working Group.
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Implementation and future modification of this International Single Species Action Plan – and all related decisions – shall be undertaken with transparency and accountability so that progress can be subject to scientific scrutiny at any time.
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Each Range State shall consider support for ‘on-the-ground’ conservation measures, particularly along the Lesser White-fronted Goose flyway(s) that traverse(s) its territory.
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Particular attention shall be paid to mortality due to hunting and urgent targeted measures shall be implemented to reduce the magnitude of this threat, the success of which shall be promptly and regularly reviewed and evaluated.
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Supplementing wild populations with captive-bred birds shall be considered if other conservation measures are not as quickly efficient as needed and should populations continue to decline. As with any other captive breeding, reintroduction or supplementation initiatives this project will be subject to consideration and practical advice by the Committee for captive breeding, reintroduction and supplementation of LWfG in Fennoscandia (see below).
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The SSAP should be regularly adapted and updated every 5 years.
1. Biological Assessment
1.1 General Information
The Lesser White-fronted Goose
Anser erythropus is the smallest
of the geese in the genus Anser. The species is globally threatened, being recognised as Vulnerable by IUCN – The World Conservation Union (IUCN, 2006), and ranked by BirdLife International as ‘SPEC 1’ within Europe, denoting a European species of global conservation concern (BirdLife International, 2004). It is listed on Annex 1 of the European Council Directive of April 2 1979 on the conservation of wild birds (79/409/EEC), in Column A of the Action Plan under the African-Eurasian Migratory Waterbird Agreement (AEWA) and in Annex II ‘Strictly protected species’ of the Bern Convention.
Lesser White-fronted Geese are long-distance Palearctic migrants, currently breeding discontinuously in the sub-arctic zone from northern Fennoscandia to eastern Siberia. The wintering/staging areas and migration routes are only partially known – see Figure 1.
Figure 1. Global distribution of wild populations of Lesser White-fronted Goose for the period 2000–2005. Dashed lines show the linkages between breeding and wintering areas for the Eastern main population, but the precise migration routes followed are unknown.
©copyright BirdLife Norway
Four subpopulations can be recognised, three of which (‘Fennoscandian’, ‘Western main’ and ‘Eastern main’ – see section 1.2 for further explanation) are surviving components of the species’ formerly more extensive breeding range (Fox 2005, Lorentsen et al. 1999). The fourth subpopulation has been created by the release of captive-bred birds within the former range of the Fennoscandian population in Sweden and by the establishment of a human-modified flyway. Two of the three wild subpopulations (‘Fennoscandian’ and ‘Western main’) underwent significant declines during the twentieth century and continue to decrease, due primarily to hunting pressure and habitat loss along migration routes and in wintering areas, though a lack of systematic count data makes calculation of reliable trends difficult for the Western main subpopulation. The reintroduced population appears to be increasing slowly and shows
high adult survival rates, but views differ markedly in relation to the ethical and scientific merits of captive breeding, reintroduction and flyway establishment or modification as conservation tools, particularly with regard to the desirable timing for applying such measures.
Among existing overview documents are the 1996 International Action Plan prepared for BirdLife International on behalf of the European Commission (Madsen 1996) and a synthesis report prepared for the Scientific Council of the Convention on Migratory Species (UNEP/WCMC 2003). Both of these documents have been fully taken into account in preparing the present Action Plan. An internet portal
www.piskulka.net (operated by the Fennoscandian Lesser White-fronted Goose Conservation Project) provides regularly updated news, links and literature references for all matters concerning wild Lesser White-fronted Geese. The implementation and effectiveness of the 1996 Action Plan were evaluated as part of a 2004 review of species action plans for Europe’s most threatened birds. This concluded that while implementation of the Lesser White-fronted Goose Action Plan had made significant progress within the EU, losses due to hunting remained high in non-EU countries, especially Kazakhstan and Russia (Nagy & Crockford 2004; see also Nagy & Burfield 2006 for a summary of ‘lessons learned’ for species action plans).
Lesser White-fronted Goose conservation has been regularly raised during international meetings held e.g. in Odessa, Ukraine (March 2004), Edinburgh, UK (April 2004) and Xanten, Germany (January 2007). A meeting exclusively dedicated to
the LWfG took place in Lammi, Finland, in April 2005. The technical presentations and discussions have been drawn on in preparing this Action Plan.
1.2 Taxonomy
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Tribe: Anserini (Vigors, 1825)
Species: Anser erythropus (Linnaeus 1758)
Synonym: Anas erythropus (additional synonyms may be found at http://www.worldbirdinfo.net/)
No subspecies are recognised. However, genetic studies (Ruokonen et al. 2004; Ruokonen & Lumme 2000) suggest that there are three distinctive populations in the wild that can be traced back to the last ice age and which should therefore be treated as three discrete management units for conservation purposes. This position is not accepted by some other stakeholders, who argue that these three populations are artefacts, resulting from recent fragmentation – due to adverse human impacts – of a once continuous population, though there is no published scientific evidence supporting this position. Recent studies show that there is a degree of genetic exchange between the Fennoscandian and Western main populations (Ruokonen et al. 2007), but still it is justified to treat these two populations as separate management units.
In this Action Plan the three populations/subpopulations are referred to for convenience as the:
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Fennoscandian population (breeding in the Nordic countries and the Kola Peninsula of north-westernmost Russia);
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Western main population (nesting in northern Russia to the west of the Taimyr Peninsula); and
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Eastern main population (nesting from the Taimyr Peninsula eastwards and wintering in China).
This Action Plan deals with conservation of two of the three wild populations – namely the Fennoscandian population and Western main population. Given that the Eastern main population does not occur within the AEWA Agreement Area or the territory of Member States of the European Union, it is only mentioned when a global context or comparison is required. The Action Plan also takes into account a fourth population, derived from captive-bred birds and used for restocking in Swedish Lapland (for population descriptions see chapter 1.3).
1.3 Population Development
Global population trend
The global population of Lesser White-fronted Goose has declined rapidly since the middle of the 20
th century. The decrease in numbers has been accompanied by fragmentation of the breeding range and is continuing to affect all populations, giving rise to fears that the species will go extinct unless the downward trend is halted and reversed. Overhunting and habitat loss are considered to be the main threats (e.g. Madsen 1996; UNEP/WCMC 2003; Fox 2005). These and other threats are described in detail in section 3.3. The global population decline is ongoing; BirdLife International estimates a decrease in numbers in the range of 30% to 49% during the period 1998–2008.
Global population estimate
The most recent estimate of the global mid-winter population is 28,000 to 33,000 individuals, derived from combining estimates for the two western populations (Fennoscandian and Western main) = 8,000 to 13,000 individuals, and the Eastern main population = 20,000 individuals (Delany et al. 2008, Delany & Scott 2006). This compares with previous published global estimates of 25,000 to 30,000 individuals (Lorentsen et al. 1999) and 22,000 to 27,000 (Delany & Scott 2002). The estimate for the Western main population is based on autumn surveys in the staging
area in Kustanay region, north-west Kazakhstan (Tolvanen & Pynnönen 1998, Tolvanen & al. 2000). The estimate for the Eastern main population (14,000) published in Delany & Scott (2002) was an underestimate, because at the most important wintering site (East Dongting Lake nature reserve) alone, up to 16,600 individuals were counted in 2004 (Barter 2005). In spite of an increased population estimate owing to improving knowledge, both Eastern and Western main populations are considered to be declining (Delany & Scott 2006).
The crash in numbers and contraction in range of the Fennoscandian population is well documented (see below), but less detailed information is available for either the Western main or Eastern main populations, which breed in Russia.
Western main population
The known breeding areas are indicated in Figure 1. The most recent population estimate for the European tundra is 500 to 800 birds. Decreasing numbers and a contracting distribution have been noted within study areas in this region, even though no significant changes/impacts have been observed on the breeding grounds (Morozov & Syroechkovskiy, 2002). However there is a fundamental lack of baseline information; for example, Syroechkovskiy et al. (2005) underline the fact that the breeding grounds of some 8,000 birds of the subpopulation have yet to be located.
Fennoscandian population
The wild Fennoscandian population in the Nordic countries (i.e. excluding the unknown number of birds nesting in the Kola Peninsula of westernmost Russia – see below) was estimated in 2004 at only 20-30 breeding pairs
and there has been a sustained, statistically significant, negative trend in the population in the period 1990-2003
1 (Tolvanen et al. 2004b; Aarvak & Øien 2004). This continues a long-term decline, from an estimated 10,000 individuals in the early twentieth century (Norderhaug & Norderhaug 1984). Breeding observations of the original wild population in Sweden were made in 1991. Footprints of adults and young were seen at a suitable locality in 1996 (Pääläinen & Markkola 1999), and a male showing breeding behaviour was seen in the same area in 1998 (A. Andersson, M. Björkland pers. comm.). In Finland, nesting was last confirmed in 1995 (Øien et al. 2001), though birds continue to be seen close to potential breeding areas virtually annually (P. Tolvanen pers. comm.). Figure 2 shows the overall trend in the Fennoscandian population over 25 years, but note that during the latter part of this period there was little organised searching for breeding birds in Finland and none in Sweden (P. Tolvanen pers. comm.). However, survey work in northern Sweden in 2005 generated two records for the spring migration period (end of April) and two records during the breeding season (June/July), but without any evidence of nesting (M. Björkland, pers. comm.). Figure 3 shows the contraction in range from the 1950s to the present day.