By Joseph Robertia
Clam shovels will have to stay buried in the garage for another summer, as the clams of eastern Cook Inlet beaches will be off limits once again in 2016.
The Alaska Department of Fish and Game presented its findings from the past summer’s razor clam surveys during a Board of Fish meeting in Anchorage late last month, and the results are a continuation of the ban on harvesting these bivalves through 2016, and possibly longer.
“We learned that from 2014 to 2015, natural mortality for mature-sized razor clams was 54 percent at Ninilchik, and abundance of mature-sized razor clams at all five beaches remained at historic low levels,” said Carol Kerkvliet, assistant area manager with Fish and Game in Homer.
The five beaches are Clam Gulch north and south, Ninilchik north and south, and what Fish and Game refers to as the “oil pad access beaches” that lay between Clam Gulch and Ninilchik.
“In terms of what is causing the problem, we don’t have a silver bullet. There was no harvest on those beaches in the past two years, so that would seem to point to some environmental factor or factors,” Kerkvliet added.
The collapse of the razor clam colonies along the eastern Cook Inlet beaches began several years ago, and some speculated that a huge storm in the fall of 2010 might have started the problem. High winds and substantial waves lashed the beaches and uprooted thousands of clams in Ninilchik, depositing them along the high tide line. As the water receded, they died from exposure in the below-freezing temperatures.
However, Kerkvliet said that in surveys reported the following summer, in 2011, some of the highest clam densities ever were recorded for Ninilchik, with 1,212,311 at the north beach and 1,621,765 adult-sized razors on the south beach.
But by 2013, it was clear razor clam numbers were waning, by as much as 95 percent. Fish and Game issued an emergency order slicing the bag limit of razor clams taken along all beaches from Kenai to Homer from 60 down to 25 clams, but the summer survey that year revealed only 65,688 adult-size clams at Ninilchik’s south beach.
The following two years, Fish and Game nixed razor clam harvests altogether, but the bivalves still seem to be struggling to rebuild their numbers. In 2015, Fish and Game surveys found only 69,934 adult-sized razors at Ninilchik’s south beach.
Juvenile-sized clams haven’t fared much better, according to Kerkvliet.
“Abundance of juvenile-sized razor clams remained at historic low levels at Ninilchik and Clam Gulch beaches,” she said. According to surveys, in 2015 there were 332,750 and 321,564 juveniles recorded at Clam Gulch north and south beaches, respectively, and 43,161 and 33,208 at Ninilchik north and south beaches, respectively.
There was promise in the middle area though.
“At Oil Pad Access North Beach, a large number of young-of-the-year clams were observed in the abundance survey and resulted in the highest estimate of juvenile-sized razor clams from any of the beaches,” Kerkvliet said, citing 1,058,755 juveniles recorded there this past summer.
It will take time for these and other clams to grow, though. While it is primarily water temperature that triggers adults to breed, typically most of the spawning happens in July or August, and it is a fairly impersonal endeavor.
“A female will broadcast six million to 10 million eggs, where they may be fertilized — by chance — by a male who has broadcast his sperm,” Kerkvliet said. This number might sound like a lot, but she added that clams are similar to salmon in that it is only a small percentage that make it to maturity.
Egg and sperm do not always meet up in the volatile currents of Cook Inlet. When they do, the embryos need to settle safely into the sand and remain protected and nourished while they grow.
“It takes around two to three years for them to grow to the size to be mature enough to then spawn themselves,” Kerkvliet said.
Water salinity, water temperature and other changes in habitat, as well as other factors (such as storms or harvest) can affect or kill young, growing clams but Kerkvliet said that this hasn’t been the case in recent years.
“We haven’t been able to detect any of these changes as leading to this low productivity, and the west-side Cook Inlet clams are still doing well,” she said.
Fish and Game will continue the harvest closure as well as summer monitoring until the east-side population rebounds.
“We want to give them every chance to spawn and replenish their numbers,” Kerkvliet said. “Like everyone else, we’re hoping they come back.”