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General Columbia River Smelt
Forecast for 2003
See also: Columbia/Cowlitz
Smelt Fishing Reports
Based on the poor parent returns observed in 1998-2000, the outlook for the 2003 smelt run could be well below average again; however, smelt have very high fecundity rates and ocean rearing conditions are likely the overriding factor in determining stock abundance for the upcoming year, as was the case in 2001 and 2002. It is important to note that ocean conditions off the Oregon and Washington coasts have improved significantly in the last three years.
The Pacific Decadal Oscillation (PDO) index based on North Pacific sea-surface temperature and pressure correlates with changes in northeast Pacific marine ecosystem productivity. Warm PDO eras have coincided with enhanced coastal ocean biological productivity in Alaska and inhibited productivity off the west coast of the contiguous United States, while cold PDO eras have coincided with the opposite north-south pattern of marine productivity. Pacific climate changes observed from late 1998 through the present indicate that the warm era that began in 1977 may have ended.
Recent trends in eulachon abundance also follow another measure of ocean climate, the tropical Southern Oscillation Index (SOI), dominated by El Nino and La Nina events. In 1977, the index changed from a regular oscillation of El Nino and La Nina anomalies to fairly persistent El Nino conditions continuing up to 1989-1990. Eulachon returns were variable during this time. The period of 1990-1997 was dominated by extreme and persistent El Nino conditions and during this time eulachon returns saw a precipitous decline starting in 1993-1994 and remained at record low levels through 2000. Since 1997 La Nina conditions have dominated and eulachon returns sharply increased beginning in 2001. The sharp decline and subsequent increase in spawner abundance lag the onset of persistent El Nino and La Nina conditions by about three years which is the assumed life cycle of most eulachon. Eulachon returns to the Columbia River in 2001 and 2002 were the largest since 1993.
The bycatch of eulachon in the West Coast Vancouver Island annual spring shrimp surveys increased significantly in 2000 and 2001 and the 2002 eulachon biomass indices were approximately 12-times the 1994-1999 average. Other pelagic fish such as anchovy, sardine, and herring all exhibited significant abundance increases during the summers of 1999-2001. Additionally, salmonid returns to the Columbia River have generally been at near record high levels during 2001 and 2002 which also suggest an improvement in ocean rearing conditions. The strong smelt returns to the Columbia River in 2001 and 2002, plus large abundances of other ocean rearing species during the same time period would suggest that smelt have recovered and would predict a large return in 2003.
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