Overfishing, habitat degradation, and other factors have contributed to the listing of multiple north american sturgeon species as threatened or endangered

This $466,615.47 federal Project Grant from the U.S. Department of the Interior Fish and Wildlife Service Region 3 under the Fish and Wildlife Management Assistance program (CFDA 15.608) was awarded to Michigan State University for a 3-year period beginning January 1, 2024.

The objectives of the grant are to: 1) develop rapid and accurate diagnostic assays to detect Lake Sturgeon Herpesviruses (LSHVs), 2) elucidate the pathogenesis and host tissue targets of LSHVs in Great Lakes Lake Sturgeon, 3) determine the prevalence and range of LSHV infections in wild and hatchery-reared Great Lakes Lake Sturgeon, and 4) determine effective UV treatment doses to inactivate LSHVs and reduce transmission risk in the hatchery environment. The grant supports research aimed at addressing concerns from federal, state, and tribal agencies about the risks these newly discovered viruses pose to Lake Sturgeon conservation and restoration efforts in the Great Lakes basin. The findings will be published in peer-reviewed journals and presented at regional and national meetings to benefit Great Lakes fishery managers and fish health professionals.

Likewise, lake sturgeon (LST), the only great lakes (GL) indigenous sturgeon species, is currently being considered for listing under the endangered species act. Despite substantial resources being devoted toward the restoration and conservation of this iconic species, little was known about their infectious diseases and what role they may be playing in population declines. However, between a recently completed great lakes fish and wildlife restoration act funded study and other efforts, we characterized two never-before described lake sturgeon herpesviruses (lshv) in wild adult LST inhabiting multiple great lakes watersheds and marking the first time a virus has been isolated from GL-LST. Both viruses were linked to skin damage in infected adults ( 15 prevalence at some sampling sites). Concerningly, lab experiments revealed juvenile LST immersed in water containing the lshv-2 became diseased and suffered cumulative mortality exceeding 33 (compared to 0 in mock-exposed and identically handled fish johnston ET AL. 2022). Further, the virus was RE-isolated from the diseased LST, proving that lshv-2 is capable of inducing disease and death in experimentally exposed juvenile LST. In light of these very recently published and communicated findings, federal, state and tribal fisheries management agencies (e.g., united states fish and wildlife service, michigan and wisconsin departments of natural resources, little traverse BAY band of odawa indians, fond DU LAC band of lake superior chippewa) have communicated substantial concerns about the risks these newly discovered herpesviruses pose to previous and ongoing GL-LST declines and restoration efforts. Given the immunosuppressive and often lifelong infections that herpesviruses cause in other animal species, as well as the risk for transmission from infected parents to offspring, how can fisheries managers most effectively prevent lshv transmission during artificial spawning and hatchery-rearing how can fish health professionals more rapidly and accurately detect and diagnose lshv infections to guide management interventions more effectively and how widespread and prevalent are lshv infections in wild and hatchery-reared GL-LST, especially given that streamside rearing facilities (srfs) raising GL-LST are often populated with gametes collected from wild adults objectives: 1) to develop rapid and accurate laboratory- and field-based diagnostic assays to detect lshv infections 2) to elucidate the pathogenesis and host tissue targets of lshvs in GL-LST 3) to determine the prevalence and range of lshv infections in wild hatchery-reared GL-LST and 4) to determine in vitro ultraviolet (UV) ZAP doses that efficaciously inactivate lshvs. Completion of the proposed objectives will enhance GL-LST restoration efforts in the short and medium, and, longer term, will provide a platform from which future lshv prevention strategies (e.g., vaccine development) can be launched. Deliverables: 1) great lakes fishery managers and fish health professionals clinicians will be equipped with newly developed, sensitive, rapid, and accurate lab and field (i.e., streamside) -based diagnostic assays for the detection and diagnosis of lshvs 2)UV treatment efficacy data that are critical for reducinglshv transmission risk in the hatchery environment, which is of direct and immediate relevance to lake sturgeonstreamside rearing efforts in the great lakes and that is completely unknown for lshvs 3) research findings will be published in peer-reviewed professional journals such as the journal of aquatic animal health, north american journal of fishery management, and transactions of the american fishery society, and 4) present findings at regional and national meetings, and to partners in the great lakes basin.