Diving Right In

Shortnose and Lost River suckers are two species endemic to the upper Klamath basin.  They are relatively slow growing and long lived, with maturation times of 5 and 8 years and average lifespans of 12 to 20 years.  Historically there were hundreds of thousands of each species living in upper Klamath lake.  Their abundance and large size (max length of about 2 feet) made them a reliable and culturally important food source for the native American tribes.  Now, with a host of different factors negatively affecting their survival, both species are federally listed as endangered.

In 2016, in an effort to prevent both species from going extinct, the US Fish and Wildlife service partnered with Gone Fishing, a local business that specialized in rearing tropical aquarium fish, to start a propagation and rearing program for Lost River and shortnose suckers.  This partnership was ideal for several reasons.  First, there was an already existing facility with ponds and a geothermal water source that proved to be useful with controlling water temperatures over winter.  Second, the owner had decades of experience and expertise with rearing and propagating fish which has contributed a great deal to the success of the program.  Third, the partnership with a local small business helps the program gain support from the general public, where the economy is largely based on agriculture.  Efforts to protect endangered fish are not always welcomed if it means restricting water use for irrigation.

This effort is unique in that unlike the hatchery programs of the past, which supplemented the wild populations with fish hatched from a captive broodstock, this program captures wild larvae as it is drifting downstream.  This does not significantly impact the wild population because the adult suckers are spawning successfully.  The population bottleneck happens during the early juvenile stage in the first 1 or 2 years of life.  The larval fish are started off in glass aquaria for the first few weeks and fed a diet of brine shrimp.  The glass tanks are useful for monitoring the larval fish for disease.  After the fish outgrow the tanks they are transferred to .1 acre earthen ponds, built to try and mimic their natural environment.  They are raised in these ponds for 2 years, after which they are collected, weighed, measured, tagged, and released.

This spring, the first 2 weeks of April, the first cohort of larval fish captured were released back into the wild.  It will be several years before we know if these fish actually make it to reproduce, but the release was celebrated as a proof of concept, there was 99% survival to the release stage.  The program is now gaining a lot of attention and support, from congressional leaders to local farmers and other water users who view this as an opportunity to allow the downlisting of the species, leading to fewer water restrictions.  That could mean more funding and an expansion of the program, as well as higher stakes for delivering concrete results.  Let’s hope we can meet these high expectations.

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