Pathways of spread, early detec2on and early response to zebra mussels in Minnesota

Transcription

1 Pathways of spread, early detec2on and early response to zebra mussels in Minnesota Michael A. McCartney, Ph.D. Research Assistant Professor January 20, 2015 Aqua/c Invaders Summit St. Cloud, MN

2 Thanks UMN Grace Van Susteren (field assistant) and Sarah Peterson (lab assistant) MN DNR: Gary Montz, Keegan Lund, Mark Ranweiler, Dan Swanson, Tom Jones & Eric Jensen, Rich Rezanka (and many staff) Minnehaha Creek Watershed District: Eric Fieldseth and staff Clean Water Fund, ENRTF, Gull Chain of Lakes Associa2on, Pelican Lakes Associa2on for funding

3 Outline The zebra mussel research program at the University of Minnesota Iden[fying pathways of spread in MN Evalua[ng spread mechanisms downstream dri^ Developing alterna[ves for early detec[on Developing and evalua[ng early response efforts

4 Research on zebra mussel invasion pathways in MN Rates and pa_erns of spread suggest that invasion pathways in Minnesota differ from those in Great Lakes states Iden[fying pathways can target preven[on

5 Pathways connect invasions from source to des[na[on waterbodies Candidate sources: Mississippi River, Lake Michigan, Mille Lacs Lake, Lake Superior Des[na[ons: e.g. lakes Zumbro, Prior, Minnetonka, Alexandria area, Maple (Douglas), Pelican (O_er Tail), Mille Lacs, Gull, Pelican (Crow Wing), Ossawinamakee, Sand (Itasca), Pike

6 Gene[c studies of invasion pathways Adult mussels genotyped at A dozen microsatellite DNA markers (used in human paternity; fisheries stock analysis) 100s to 1000s of Single Nucleo/de Polymorphism (SNP) markers SNPs used in crop plant gene[cs (mapping) SNP genotyping in collabora[on with UM Genomics Center

7 Data analysis: gene[c clustering Duluth Harbor From Brown and Stepien (2011) Lake Pepin North American source popula[ons are gene[cally dis[nguishable (including 2 candidate sources in MN)

8 Tes[ng invasion pathway scenarios Time Upper Miss L Ossie/ Pine R Mille Lacs Scenario I: Stepping- stones inland Preven[on: target boat traffic between inland lakes Minne tonka Scenario II: Chronic reintroduc[ons Time L Ossie/ Pine R Mille Lacs Minne tonka Preven[on: increase surveillance of chronic sources (e.g, Mississippi boat ramps, or sources out of state)

9 Spread mechanisms: downstream dri^ Veliger larvae allow rapid spread within lakes and down large rivers But down small streams (Horvath & Lamber[ 1999)? Perhaps not MN assumes that lakes connected by small streams to ZM lakes will be infested we need to evaluate this assump[on

10 Downstream dri^ studies in Minnesota Sampling at increasing distances downstream from the infested lake, ending near the inlet Juvenile mussels: se_lement (June- October) Veligers: water pumped and filtered through 50- micron mesh

11 Downstream dri^ results Se_lement: 2014 Pelican River: Pelican/Fish to Lizzie, O_er Tail Co. Site Distance (km) SeKlement (juveniles per block) ± 2.64 Site Site 2

12 Se_lement, 2014 Site 1 Site 2 Gull River: Gull Lake to Crow Wing River, Crow Wing County Site 3 Site Distance (km) SeKlement (juveniles/block) ± Site 4

13 Downstream dri^ results Se_lement of mussels is localized; adult popula[ons will not establish far down small streams Veliger counts show that larvae disperse farther downstream, but Their numbers decline with distance They are produced in pulses

14 Research on early detec[on The challenge: how can we detect zebra mussels before popula[ons explode in numbers? Mussels may be few and sca_ered DNR staff search Lower Hay Lake. Photo from the Pine and Lakes Journal Visual census covers limited areas, even with great effort Veliger larva counts: a sensi[ve alterna[ve

15 Veliger counts for early detec[on Strengths Detec[on before adult mussels are discovered An index of reproduc[ve output, lake- wide Current microscopy assays: quan[ta[ve & sensi[ve, but tedious and lack confirma[on From h_p:// A quan[ta[ve PCR (molecular) assay offers Species ID confirma[on in high priority cases Faster processing and greater throughput High sensi[vity (poten[ally)

16 Molecular detec[on of veligers Plankton tows (lakes) sample collec[on simpler than edna Plankton DNA is extracted in bulk Quan[ta[ve PCR of ZM and QM- specific gene fragments to detect and count larvae Check results against counts from cross polarized light microscopy

17 Early- response treatments for zebra mussels in open waters Developing open water pes[cide treatment protocols Evalua[ng pes[cide treatment methods: MAISRC Data Repository

18 Lake treatments for zebra mussels: goals Eradica[on Popula[on growth suppression Restora[on (e.g. removal from a na[ve mussel bed) Localized removal (e.g. from a beachfront)

19 Treatment agents Agent Pros Cons Zequanox (heat killed cells of Pseudomonas fluorescens) Copper products (copper sulfate, EarthTec ) Specific toxicity to zebra and quagga mussels Low or no non- target toxicity in bioassays Cheap and EPA- approved Cost prohibi[ve for large areas < 100% kill in open waters Difficult to maintain effec[ve concentra[ons Potash (potassium chloride) Track record as algaecide and molluscicide Cheap, high toxicity to zebra and quagga mussels Limited non- target effects at concentra[ons used Toxic to inverts and fish; accumulates in sediment Not yet labeled as a pes[cide Kills na[ve mussels

20 Survey and monitoring requirements For zebra mussel pes[cide treatment projects

21 Survey and monitoring required: zebra mussel pesticide treatments Toxicity tests Within treatment area, lake bottom* Within treatment area, in cages Aquarium testing Image from Marrone Bio Innovations, Inc. *Minimum requirement

22 Photos courtesy of Eric Fieldseth and Jill Bjorklund, MCWD I m dead

23 Survey and monitoring required: zebra mussel pesticide treatments Population responses # of mussels in the treatment area* # of mussels outside the treatment area* Veligers in plankton Settlement on plates Pre-treatment *Minimum requirements Image from Kylie Bloodsworth, MN DNR

24 Survey and monitoring activities: zebra mussel lake treatments Population responses # of mussels in the treatment area* # of mussels outside the treatment area* Veligers in plankton Settlement on plates Post-treatment *Minimum requirements Photo by Dan Swanson, MN DNR

25 What do we hope to learn.? What are the most effective treatment agents and methods? Is it possible to eradicate? To suppress population growth? When can we treat and prevent a zebra mussel population from exploding, and when is it too late?

26 MAISRC Lake Treatment Data Repository: Why contribute? Online repor[ng, data storage and access to details and outcomes from other treatment a_empts Opportunity to scien[fically evaluate your efforts Help further the science of ZM management Access to standardized monitoring and bioassay protocols, and training

27 Resources Ques[ons? Informa[onal literature available online from DNR (soon) Monitoring protocols also to be posted online (DNR and MAISRC) Contact MAISRC or your regional UMN Extension Office for details and training (this spring)