CURED SALMON EGGS KILL JUVENILE SALMONIDS

CURED SALMON EGG BAIT KILLS JUVENILE SALMON AND STEELHEAD

In 2007 Jeff Misler asked the Oregon Department of Fish and Wildlife to test cured salmon eggs for toxic compounds, for he was concerned juvenile salmonids were being killed by ingesting the bait.

Oregon State University and ODFW researchers conducted the study for ODFW and made the following discovery: Cured salmon eggs killed juvenile salmon and steelhead.

The research discovered that within a 23 day span 30% of the juvenile salmonids were killed. Upon further investigation, they found that eggs cured with sodium sulfite were lethal. It is this chemical that kills the fish.

They also tested the eggs by giving them a soak to see if they were less lethal. They were testing whether fishing softened their impact. Soak times ranged from 30 seconds to 10 minutes, but the results were the same: the fish died.

Salmon eggs are a favored bait used by anglers fishing for salmon and steelhead. Anglers cure their own eggs or buy them, but if sodium sulfite is used in the curing process they are fishing a poisoned bait.

Additional research on nutrient enrichment of salmon and steelhead streams has pointed out the fact that eggs are preferred by juvenile salmonids. Most salmon eggs are available in early winter months when the juvenile fish are seeking food in cold water when other food supplies are less abundant.

Juvenile fish are seeking the fat rich eggs and anglers fishing steelhead and salmon are using cured eggs. The combination is lethal.

ODFW officials said in a news release that “We’ve already talked with several manufactures and we’re encouraged by their commitment to solving this problem.”

However, ODFW researchers said they “…cannot predict what impact, if any, the ingestion of cured eggs by juvenile fish has on the final size of the adult population.”

In the research proposal to investigate the toxic effect of cured salmon eggs on juvenile salmonids, there is evidence of even more mortality than what was found in the OSU research. A 1979 study showed that consumption of borax cured eggs led to decreased growth and an increase in plasma corticosteroids in chinook and rainbow trout juveniles. Furthermore, we recently observed between 50-60% mortality in a preliminary study feeding cured salmon eggs (Clements Pers Obs).

Measuring the impact based on the effect on adult salmon and steelhead production, is like taking pins out of the voodoo doll. They can reason that not all juveniles survive to return as adults, so the loss of a few or even a gob of young fish is, at best, immaterial and mitigates any need to manage the use of eggs as bait.

At a time when most of our wild salmon and steelhead are depleted and designated a threatened species, sensitive species, and candidate species for ESA-listing, one would hope that the management authorities would recognize a problem rather than trying to minimize it.