Thursday, May 9, 2013

Comment Period Reopened for Proposed Listing of the Spring Pygmy Sunfish as Threatened

The U.S. Fish & Wildlife Service (USFWS) has reopened the public comment period on the proposal to list the Spring Pygmy Sunfish (Elassoma alabamae) as threatened with critical habitat designated. (http://www.gpo.gov/fdsys/pkg/FR-2013-04-29/pdf/2013-09974.pdf). Public comments were reopened primarily due to 1) a slight reduction in proposed critical habitat (private property was inadvertently included in first proposal) and 2) a draft economic analysis is now available for review.

The Spring Pygmy Sunfish (Elassoma alabamae). Photo by Bernie Kuhajda.
Spring Pygmy Sunfish are restricted to springs and spring-fed creeks along a five-mile length of Beaverdam Creek in northern Alabama near Huntsville. This species was historically known from two other spring systems in the Tennessee River drainage in Alabama, but habitat destruction from dams, reservoirs, and herbicides caused these populations to disappear. It only reaches 1 inch, lives for a year, and needs clear spring water and dense submerged vegetation.  Spring Pygmy Sunfish are reliant on their vision to find food and mates, so clear water is essential.  The dense submerged vegetation is needed for the eggs to be successfully laid, hatched, and for juveniles and adults to hide from predators. These life history traits make the species vulnerable to habitat disturbances that muddy the water, herbicides that reduce or kill aquatic vegetation, and groundwater withdrawals. Lower water levels, together with drought conditions, have caused springs in the system to go completely dry.

Beaverdam Spring, ideal habitat for the Spring Pygmy Sunfish. Photo by Bernie Kuhajda.
Spring Pygmy Sunfish habitat in the Beaverdam Creek system is highly imperiled due to the rapid growth of nearby Huntsville (http://www.sasaki.com/project/227/huntsville-western-expansion-annexed-property-master-plan/) and an increase in agricultural and municipal groundwater pumping in the aquifer that feeds these springs. Construction projects with no or improperly installed silt fences and an increase in impervious surfaces that produces heavy stormwater runoff threaten water quality.

Ineffective silt fences along Beaverdam Creek that contribute to the siltation of critical habitat for the Spring Pygmy Sunfish. Photo by Mike Sandel.
Impervious surfaces also threaten water quantity by deflecting water that would normally recharge the underlying aquifer. These are just some of the escalating threats that Beaverdam Creek and the Spring Pygmy Sunfish are facing.

USFWS had determined that listing the Spring Pygmy Sunfish as threatened rather than endangered is warranted primarily due to conservation measures in a candidate conservation agreement with assurances (CCAA) between USFWS and Belle Mina Farm, Ltd. This company owns Beaverdam Spring, by far the largest spring in the system. However this CCAA gives no protection to the majority of the critical habitat and can be terminated at any moment. The Spring Pygmy Sunfish is restricted to one creek system, is totally reliant on groundwater, and there is an imminent threat of urbanization/industrialization within the recharge area of the aquifer. This led the Southeastern Fishes Council to consider the Spring Pygmy Sunfish as one of the Desperate Dozen, one of the 12 most critically imperiled fish species in the southeast (http://www.sefishescouncil.org/proceedings/sfcpro51.pdf). I personally think the Spring Pygmy Sunfish should be listed as endangered based on the best available science.

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