Íslenskar landbúnaðarrannsóknir - 01.09.1978, Page 49
ÍSL. LANDBÚN.
J. AGR. RES. ICEL. 1978 10,2'. 47-56
Spawner-recruit relationship
in Ellidaár
Philip r. Mundy,
College of Fuheries,-JJniversily of Washinglon, Seatlle.
Marianna Alexandersdóttir,
and
Guðný Eiríksdóttir
Inslitute of Freshwater Fisheries, Reykjavík.
ABSTRACT
Ellidaár is the only stream in Iceland for wich data exist to construct spawner-recruit relationships. A two
parameter Ricker curve was fitted to all data for two separate periods. The model predicts that the return
per spawner will decrease with increased escapements and vice versa as confirmed by the actual observa-
tions.
INTRODUCTION.
The Ellidaár flows into the Faxa Bay in
southwestern Iceland. It is the outlet of
the presently impounded Ellidavatn
(64°N, 22°W), which is 74 m above sea
level. The river is six kilometers long with
a drainage area of 280 km and is classified
as a direct run-off, springfed and lake
stream (National Authority 1969). The
flow is variable and the river is subject to
flooding in February and March every
year(1962, 1968, and 1969 were especially
bad floods).
The scheme below gives a concise his-
tory of the Ellidaár:
Year Event
1890 Fishing gear restricted to
rods only.
1906 City of Reykjavík buys river
and leases out fishing.
1913 Daily reading at the flow
gauging station begins (1924
- autamatic recorder instal-
led).
1918- 1921 Power dam construction at
Arbaer, one kilometer up-
stream from river mouth.
1919- 1929 South tributary still open to
salmon run.