DOI: 10.5061/dryad.jm63xsj98
title: Anadromous cataloging and fish inventory in select drainages of the Upper Tanana and Yukon Rivers 2019

description: During the summer of 2019, Alaska Department of Fish and Game Division of
 Sport Fish staff conducted a rapid systematic inventory
 of anadromous fish distribution and associated aquatic and riparian
 habitat in select drainages of the upper Yukon River and Tanana River.
 Target streams will be selected to fill gaps in coverage of the State of
 Alaska's Catalog of Waters Important for the Spawning, Rearing or
 Migration of Anadromous Fishes (AWC) for freshwater habitats expected to
 support anadromous fish populations likely to be impacted by human
 activities. Two crews sampled standardized target stream reaches using
 electrofishers with sufficient effort to collect all species (perhaps with
 the exception of rare species) of the extant fish community. At each
 sampling site, crews documented standard aquatic and riparian habitat
 characteristics. For each water body in which anadromous fish are
 observed, nominations to the AWC were submitted. One hundred sites were
 surveyed during this study period, a slightly smaller number than what was
 expected due to long term drying patterns in the region that led to
 farther travel times in addition to flooding events that happened after
 heavy rains.
description: Following ADF&G's AFFI protocols, two crews, each
 with two members, will simultaneously sample fish communities in selected
 study stream reaches for approximately 20 days during the summer of 2019.
 Target survey sites will include wadeable headwater streams sampled with a
 backpack electrofisher and un-wadeable streams (including mainstem rivers)
 sampled with a raft mounted electrofisher. Two helicopters will provide
 access to the stream study sites for headwater and cataraft crews. Sites
 within the study area that have the highest potential for habitat
 degradation will be identified through consultation with the ADF&G
 Division of Habitat and will be given a higher sampling
 priority. The number of headwater streams in the study
 area will exceed the project’s limited sampling effort capacity;
 therefore, a subset of mapped streams, comprising the longest stream
 segments not currently listed in the AWC, will be selected as target
 streams. The headwater team will sample approximately six to eight
 headwater streams per day and the raft team will float and sample one
 un-wadeable stream per day, including a reach from all mainstem rivers in
 the study area.  Sampling
 methods At selected streams, the fish
 community will be sampled with standardized methods and effort according
 to AFFI protocols. Fish will typically be collected by single-pass
 electrofishing (other non-lethal gear types such as beach seines, angling,
 or minnow traps may be deployed if conditions prohibit safe or effective
 electrofishing). Electrofishing is the principal fish collection gear
 because it is recognized as the most comprehensive and effective method
 for collecting fish in lotic systems.  At all target
 streams, a length of stream (referred to as a reach) standardized by
 stream width (i.e., 40 or 120 wetted-channel-widths in wadeable and
 un-wadeable target streams, respectively, or, in large rivers, the maximum
 length of stream that can be sampled in one day) was sampled to include
 all aquatic habitat types within that reach. Collected fish will be
 identified to species, tallied, measure for fork length, and examined for
 external abnormalities. Additionally, standard water chemistry, channel
 morphology, and riparian habitat parameters will be recorded at each
 sample site. To enhance data quality and completeness and data entry
 efficiency, all collected data will be entered each day into an integrated
 database installed on a notebook computer.
description: For alternative visualization of the data, see the interactive
 mapping feature at:
 http://www.adfg.alaska.gov/index.cfm?adfg=ffinventory.interactive