Kenai National Wildlife Refuge Aquatic Invasive Plant Surveys 2023

Matthew Bowser; Kristine Inman; Nathan Davis; Kristian Merrell; Beth Sullivan; Dom Watts; Chris Snyder; Sean Wise; Ethan Bowser; Shealyn Imgarten

doi:10.15468/h79pjm

Kenai National Wildlife Refuge Aquatic Invasive Plant Surveys 2023

Citation

Bowser M, Inman K, Davis N, Merrell K, Sullivan B, Watts D, Snyder C, Wise S, Bowser E, Imgarten S (2023). Kenai National Wildlife Refuge Aquatic Invasive Plant Surveys 2023. Version 1.8. United States Fish and Wildlife Service. Occurrence dataset https://doi.org/10.15468/h79pjm accessed via GBIF.org on 2024-12-15.

Description

To maintain biological integrity, biological diversity, and native fish resources in Kenai Peninsula freshwater systems, we surveyed for invasive elodea in Kenai Peninsula lakes using rakethrow surveys.

Sampling Description

Study Extent

Our target universe was the set of all waterbodies in the study area susceptible to invasion by non-native plants, particularly elodea. Our initial sample frame was the set of lakes in the vicinity of the Kenai National Wildlife Refuge. We considered individual lakes to be the sampling units.

Sampling

We selected 23 lakes to survey for elodea in 2023, mostly basing our selections on the prioritization of the Alaska Department of Fish and Game’s Invasive Species Lake Prioritization (Alaska Department of Fish and Game, 2022). We also took into account recent pike surveys, avoiding lakes that had been surveyed for pike in the last 10 years or where surveys are planned for 2024. We collaboratively planned with our partners, openly sharing our survey schedule. We sought to keep the number of sites sampled per lake to between 30 and 60 sampling locations per lake. We related the range of lake perimeters in our study area to this range of sample sizes with the linear formula n = mp + b, where where n was the sample size, m was 2.4 km-1, p was the perimeter in km, and b was 27. This resulted in a range of sample sizes of 30 to 63 sampling locations per lake. To select sampling points we used a Quarto document that called R, version 4.2.3 (R Core Team, 2023) and used the R packages lwgeom, version 0.2-13 (Pebesma, 2023) and sf, version 1.0-12 (Pebesma, 2018; Pebesma and Bivand, 2023). We divided the lake perimeters into segments, one segment corresponding to a target sampling location in each lake. Our rake throw survey methods were similar to the examples of Fulkerson (2022a) and Fulkerson (2022b).

Method steps

Within each pre-determined lake segment, we selected a location where elodea would be most likely to occur based on our previous experience surveying for elodea on the Kenai Peninsula. Within the larger segments, we selected protected bays and avoided exposed points. We positioned our boat off of shore, usually a little farther from shore than the limit of dense emergent vegetation, often in about 1–2 m water depth.
From the selected point the two observers threw the two rakes perpendicular to the shoreline: one rake thrown toward shore and the other out toward the center of the lake. After allowing the rakes to contact the bottom, both observers slowly and simultaneously pulled in the rakes, dragging them over the substrate. The rakes were carefully brought onto the boat, photographed, and the presence or absence of elodea was recorded. We also recorded depth, substrate types, and the presence of other aquatic plant species.

Taxonomic Coverages

We surveyed for non-native plants, especially Elodea.

Plantae
common name: plants rank: kingdom

Geographic Coverages

The geographic extent included freshwater lakes in the vicinity of the Kenai National Wildlife Refuge, Kenai Peninsula, Alaska, USA.

Bibliographic Citations

Alaska Department of Fish and Game (2022) Alaska invasive species lake prioritization. Alaska Department of Fish and Game. https://experience.arcgis.com/experience/41a6f3a3f35f4e0fae52f9c5a0c2fbd2/ - https://experience.arcgis.com/experience/41a6f3a3f35f4e0fae52f9c5a0c2fbd2/
Kenai National Wildlife Refuge & US Fish & Wildlife Service, Alaska Regional Office, Division of Conservation Planning & Policy (2010) Comprehensive Conservation Plan: Kenai National Wildlife Refuge. Anchorage, Alaska: U.S. Fish & Wildlife Service. https://ecos.fws.gov/ServCat/Reference/Profile/149784 - https://ecos.fws.gov/ServCat/Reference/Profile/149784
Fulkerson JR (2022a) Aquatic Plant and Elodea Survey in Chugach National Forest: 2021 Survey Results. Anchorage, Alaska: Alaska Center for Conservation Science, University of Alaska Anchorage, pp. 26 + appendix. -
Fulkerson JR (2022b) Aquatic Plant and Elodea Survey in Chugach National Forest: 2022 Survey Results. Anchorage, Alaska: Alaska Center for Conservation Science, University of Alaska Anchorage, pp. 21 + appendix. -
Pebesma E (2018) Simple features for R: Standardized support for spatial vector data, The R Journal, 10(1), pp. 439–446. https://doi.org/10.32614/RJ-2018-009. - https://doi.org/10.32614/RJ-2018-009
Pebesma E (2023) lwgeom: Bindings to selected ’liblwgeom’ functions for simple features. https://CRAN.R-project.org/package=lwgeom. - https://CRAN.R-project.org/package=lwgeom
Pebesma E & Bivand R (2023) Spatial data science: With applications in R. Chapman and Hall/CRC, p. 352. https://r-spatial.org/book/. - https://r-spatial.org/book/
R Core Team (2023) R: A language and environment for statistical computing. Vienna, Austria: R Foundation for Statistical Computing. https://www.R-project.org/. - https://www.R-project.org/

Contacts

Matthew Bowser
originator
position: Fish and Wildlife Biologist
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: matt_bowser@fws.gov
userId: https://orcid.org/0000-0003-4879-3997

Kristine Inman
originator
position: Supervisory Biologist
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: kristine_inman@fws.gov

Nathan Davis
originator
position: Biological Technician
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: nathan_davis@fws.gov

Kristian Merrell
originator
position: Biological Technician
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: kristian_merrell@fws.gov

Beth Sullivan
originator
position: Volunteer
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska

Dom Watts
originator
position: Wildlife Biologist/Pilot
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: dom_watts@fws.gov

Chris Snyder
originator
position: Student Conservation Association Crew
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US

Sean Wise
originator
position: Biological Intern
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: sean_wise@fws.gov

Ethan Bowser
originator
position: Volunteer
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US

Shealyn Imgarten
originator
position: Youth Conservation Corp Crew Leader
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: shealyn_imgarten@fws.gov

Matthew Bowser
metadata author
position: Fish and Wildlife Biologist
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: matt_bowser@fws.gov
userId: https://orcid.org/0000-0003-4879-3997

Matthew Bowser
point of contact
position: Fish and Wildlife Biologist
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: matt_bowser@fws.gov
userId: https://orcid.org/0000-0003-4879-3997

Kristine Inman
administrative point of contact
position: Supervisory Biologist
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: kristine_inman@fws.gov

Matthew Bowser
administrative point of contact
position: Fish and Wildlife Biologist
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
Alaska
US
email: matt_bowser@fws.gov
userId: https://orcid.org/0000-0003-4879-3997

Kristine Inman
administrative point of contact
position: Supervisory Biologist
USFWS Kenai National Wildlife Refuge
PO Box 2139
Soldotna
99669
alaska
US
email: kristine_inman@fws.gov