Fennoscandian Lesser White-fronted Goose conservation project ...

Fennoscandian Lesser White-fronted Goose conservation project – Annual report 1999
Pääläinen & Timonen: Field surveys in possible breeding areas of Lesser White-fronted Goose in Lapland and Finnmark
Field surveys in possible breeding areas of Lesser White-fronted
Goose in Lapland and Finnmark
34
Jarmo Pääläinen & Sami Timonen
North Ostrobothnia Regional Environment Centre, PO BOX 124, FIN-90101 OULU, FINLAND, e-mails: jarmo.paalainen@vyh.fi,
sami.timonen@vyh.fi
1. Introduction
The field work in Lapland in summer 1999 was divided in three
different parts: surveys in the potential breeding grounds of Lesser
White-fronted Goose (Anser erythropus, later LWfG); limiting the
Red Fox population; and offering additional food for geese. The work
was concentrated in the most potential breeding areas based on
knowledge from earlier years, and was carried out as a part of the
Finnish LWfG Life project.
The surveys were carried out by 12 survey groups formed by 23
persons, equivalent to about 10 months field work. The surveyed
area covered c. 2000 km2 in Finland and c. 500 km2 in Norway. Like
in earlier years, the teams were in the field from 2 to 20 June, and
again from 20 to 10 August, leaving the incubating and hatching
period of LWfG without human disturbance.
The surveys in Norway were carried out by three survey teams
and the areas were chosen based on earlier observations near the
Finnish border and in the eastern and western parts of Finnmark.
The teams collected all goose feathers found in the field, and
compared them with a LWfG feather formula specially made for
this purpose to verify the identification. Also, faeces of geese were
collected for later DNA analysis. Suitable LWfG breeding habitats
were photographed in order to analyse possible landscape changes.
A team visiting the core breeding area used a videocamera for this
purpose.
2. Weather conditions
The snow layer was exceptionally thick due the cold temperatures
in May and June, and when it melted rapidly the flood was huge,
complicating the field work. In July and August the surveys were
difficult due to heavy rain.
3. Observations
In June, a flock of five LWfG (probably moulting or migrating nonbreeders)
was seen in Kevo Strict Nature Reserve in northern Finnish
Lapland. In the core area, where LWfG were breeding at least until
1995, one small unidentified goose (possibly LWfG) was seen flying
with a Bean Goose (Anser fabalis). During the pre-nesting period
two LWfG (not a pair) were observed in the fields of Sirma by the
Tana River (see Tolvanen 2000, pp. 18–22 in this report). A flock of
six LWfG (flying north, possibly landing on a lake) was seen in the
former Finnish core breeding area by a frontier guard on 24
September.
Less Bean Geese and Whooper Swans (Cygnus cygnus) were
observed in 1999 as compared with 1998. Some individuals of Pinkfooted
Goose (Anser brachynchus) and White-fronted Goose (A.
albifrons) were observed during the surveys.
On the Norwegian side, only one flock of six LWfG was observed
flying north on 1 July in western Finnmark.
4. Limiting the Red Fox population
The population of Red Fox (Vulpes vulpes) has increased gradually
in the last decades in northern Finnish Lapland. The data collected
since 1989 in the former Finnish core breeding area of LWfG
indicates that the abundance of Red Foxes may significantly limit
the annual reproduction of the geese. Most of the geese seem to give
30
25
20
15
10
5
0
Goslings
r2=0.96
Foxes (ind./10 days)
0 1 2 3 4
Figure 1. Linear regression indicating the negative correlation between
the number of produced LWfG goslings and the number of Red Foxes
seen per ten observation days (p=