Freshwater pearl mussel of Karelia (assessment of present day

Transcription

Freshwater pearl mussel of Karelia (assessment of present day
Freshwater pearl mussel of the North
Ladoga Rivers
Institute of Biology Karelian research center
Russian academy of Sciences
and
Программа ПС ЕИСП Карелия, проект КА526
Major project tasks
 Studies to assess the situation with
pearl mussel populations
 Baltic drainage basin (Lake Onega &
Lake Ladoga rivers)
 White Sea drainage basin (Karelian
rivers)
Introduction
 The freshwater pearl mussel, Margaritifera
margaritifera L., is a threatened species of the
European fauna. Its conservation status is secured by
Annex II of the Bern Convention (1979) and the IUCN
Red List of Threatened Animals (1996), as well as the
Red Data Book of East Fennoscandia (1998), Red
Data Book of the Russian Federation (2001) and Red
Data Book of Karelia (2007).
 A unique feature of this mussel is its exceptionally
long life span, under subarctic conditions sometimes
longer than 140 years.
 The freshwater pearl mussel has a complex life cycle.
For embryonic development, its larvae, called
glochidia, must parasitize on the gills of salmonids,
mostly of juveniles.
Freshwater pearl mussel
(Margaritifera margaritifera)
Atlantic salmon (Salmo salar)
History
 City of Kem was established in 1785, it received a
coat-of-arms where a wreath of pearls was depicted
in the lower half of the shield, against blue
background.
 A prominent researcher of the USSR lakes, Professor
G. Vereshchagin (1930) reported Karelia to have 70
pearl-producing rivers and streams. In just 30
years however, pearl mussel populations in
most of the rivers were either lost or declined
notably.
 In the 18th century, the river famed for large pearls
was Iholanoija, in the second half of the 19th century
– River Nemena.
 At present the most known rivers in the northwestern
Russia with extant populations of freshwater pearl
mussel are the rivers Keret and Varzuga, where the
mussel populations are estimated at millions.
 There are few publications regarding present status of
freshwater pearl mussel in the rivers in Karelia (the
Kamennaya River, basin of the Kem River) and
Arkhangelsk Region (the rivers Kozha and Solza)
(Koshevarov, Nikitin, 1998; Bespalaya et al., 2007).
Kola Peninsula freshwater
pearl mussels rivers
Barents Sea
Paanajarvi
Vuokinjoki
Kamennaya
White Sea
fresh water
pearl mussel
rivers
Lake Ladoga and Onega pearl
mussel rivers
Syskyänjoki
The row data on the Margaritifera margaritifera historical
geography and recent population status in South-West Karelia
(basin of Ladoga Lake)
Water system
Kokkolanjoki
Ihalanjoki
Kitenjoki
Suomerianjoki
Syskyänjoki
Data on pearl
harvesting
No data
18th cent.
1790)
18th cent.
1790)
No data
No data
Confirmation of species
availability by
specialists
Modern population status
(21st cent.)
(19th–21st cent.)
(Kärki, 1915)
(Hermann, (Kärki, 1915)
No data
No data
(Hermann, No data
No data
Yes (Kärki, 1915)
No data
Yes
(Kärki,
1915; Young fresh water pearl
Makhrov et al., 2011)
mussels, end young
Atlantic salmons infected
with glochidia are found
(Makhrov et al., 2011,
and our project data)
Size variability of freshwater pearl
mussels in river Syskyänjoki
9
8
7
Frequency
6
5
4
3
2
1
0
24
36
48
60
72
max. Shell length (mm)
84
96
108
120
Age variability of freshwater pearl
mussels in river Syskyänjoki
112
104
Length,_mm
96
88
80
72
64
56
8
9,6
11,2
12,8
14,4
Age,_year
16
17,6
19,2
20,8
Atlantic salmon parr
The main problems
 Small number of surveyed rivers
 The dominance of the older age
groups pearl mussels
 Low density of salmon parr
 Poaching
 Trout dominance
 Dangerous condition of freshwater
pearl mussel population in Keret river
International cooperation program
«Freshwater pearl mussel in northern rivers»
Pearl mussel rivers of Karelia
Keret
Paanajarvi
Gridina
Vuokinjoki
Kamennaja
Nemina
Suna, Kivach
Pjlma
Suskianjoki
”Green belt of Fennoscandia”
 International
cooperation
”Pearl & Salmon”
based on
existing
protected areas
Thank you for your attention !

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