GLKN Fish Inventories |
Inventory of nearshore fish population densities and community structures at Apostle Islands National Lakeshore and Isle Royale National Park |
Owen T. Gorman and Seth A. Moore, USGS-BRD Great Lakes Biological Station, Ashland, Wisconsin |
Abstract: Fish communities of the nearshore waters of the Apostle Islands National Lakeshore (APIS) and Isle Royale National Park (ISRO) were studied during the summers of 2003-2004. Objectives of our study were: 1) conduct an inventory of fish species to estimate relative abundances, describe community structures, and identify distribution patterns related to habitat associations, 2) compare nearshore and offshore fish communities in APIS, 3) evaluate the efficacy of various gear to sample fish communities, and 4) provide recommendations for establishing a long-term monitoring and research program. We found the nearshore fish communities of APIS and ISRO to be dominated by a set of common native species, which included lake chub (Couesius plumbeus), ninespine stickleback (Pungitius pungitius), slimy sculpin (Cottus cognatus), burbot (Lota lota), and trout-perch (Percopsis omiscomaycus). The predominant nearshore aquatic habitat of the APIS region was characterized by low slope with sandy substrates while in ISRO was characterized by moderate to steep slopes with coarse and bedrock substrates. Most of the shoreline of APIS and ISRO was exposed to the open lake, but embayments in ISRO provided protected habitat, particularly at the head of bays. Habitat in these protected areas was characterized by low slope, fine substrates and low structure, but harbored relatively diverse fish assemblages with high relative abundances. Species indicative of these protected habitats included spottail shiner (Notropis hudsonius), blacknose dace (Rhinichthys atratulus), and white sucker (Catostomus commersoni). Unprotected areas at the mouth of bays were characterized by high slope, rocky substrates and high structure, but harbored simple assemblages dominated by lake chub. In contrast, nearshore habitat in APIS with high slope and coarse substrates harbored more diverse fish assemblages than areas of low slope and fine substrates. The offshore fish community in APIS was dominated by coregonids and distinct from the nearshore community; only slimy sculpin held a position of strong importance in both communities. At a regional scale, the similarity in composition of nearshore fish communities of APIS and ISRO suggests that the fish communities of the nearshore waters of Lake Superior are drawn from a common source pool and that differences in habitat characteristics and protection from the open lake determine the local composition and structure of those communities. The lake chub was the most distinctive feature of the nearshore fish community as it was both unique to nearshore waters and was an abundant, conspicuous member of that community. Of four gears used to sample nearshore fish communities (seines, bottom trawls, Windermere traps, fyke nets) only Windermere traps sampled fish over the full range of nearshore habitats in both APIS and ISRO. For long-term monitoring of nearshore fish communities of APIS and ISRO we recommend using Windermere traps supplemented by fyke nets and electrofishing at intervals of 1-2 years. Future research in nearshore waters should address the linkage between nearshore fish communities and that of the open lake, particularly in regard to habitat and life history associations of nearshore and offshore species, spawning and nursery areas for open water fishes, and trophic and energetic contributions of nearshore waters to the Lake Superior ecosystem. Project Status: Completed Final Report |
Fish Species Inventory of Inland Waters of Pictured Rocks National Lakeshore, Michigan |
Lee E. Newman, Ashland Fishery Resources Office, U.S. Fish and Wildlife Service, Ashland, Wisconsin |
Abstract: The US Fish and Wildlife Service (USFWS), Ashland Fishery Resources Office, conducted fish surveys of inland waters at Pictured Rocks National Lakeshore, targeting species likely to occur in the park but not yet confirmed. Using gill nets, Windermere nets, and backpack electrofishing equipment, USFWS captured 595 fish representing 21 species. The western blacknose dace (Rhinichthys atratulus) is the only new species confirmed during this survey. The researcher provided recommendations for further intensive sampling of targeted species and routine monitoring for new species. Project Status: Completed Final Report |
Inventory of Nearshore Fishes at Pictured Rocks National Lakeshore |
Henry Quinlan and Lee Newman, USFWS Ashland Fishery Resources Office, Ashland, Wisconsin |
| Abstract: Fish species assemblages in the nearshore waters of Lake Superior vary substantially, both spatially and temporally. Water temperature and movement of anadromous species both strongly influence the species present at a given time and location. The objective of this study is to determine the presence and abundance of fish species and mudpuppy (Necturus maculosus) occupying Lake Superior waters off Pictured Rocks National Lakeshore. Sampling was conducted over 3 one week periods, with one week each in spring, summer, and autumn, 2002. During each sampling period, bottom trawling, gill nets, trap nets, beach seines, and electrofishing were used. Captured fish were counted and measured. Twenty-nine fish species and one hybrid (splake) were captured. No mudpuppies were collected. Nine of the 29 collected species, as well as the hybrid, had not previously been confirmed in the Lakeshore’s waters. Fish species known to occur in nearshore waters of Lake Superior, but which were neither captured nor observed at the Lakeshore during this or previous surveys, are lake sturgeon (Acipenser fulvescens), shorthead redhorse (Moxostoma macrolepidotum), pygmy whitefish (Prosopium coulteri), and common carp (Cyprinus carpio). The inability to detect these species, and the mudpuppy, may be due to limited habitat. Pictured Rock National Lakeshore lacks warm, fertile, shallow bays favored by many fishes, and also lacks soft, silty substrate preferred by the mudpuppy.
Project Status: Completed Final Report |
Inventory of Inland Fishes at Sleeping Bear Dunes National Lakeshore |
Sleeping Bear Dunes National Lakeshore, Empire, Michigan, Grand Traverse Bay Band Ottawa and Chippewa Indians Natural Resources Department, and U.S. National Park Service, Great Lakes Inventory and Monitoring Network, Ashland, Wisconsin |
| Problem Statement: A survey
of fishes at Sleeping Bear Dunes National Lakeshore has not
been conducted since 1979. Since this 1979 survey, zebra mussels
(Dreissena polymorpha) have invaded the Lakeshore. In the late
1980s, zebra mussels first invaded Lake Michigan and by 1995,
piles of the mussels washed up on the beaches of the Lakeshore.
The zebra mussels then spread to some of the Lakeshore's inland
lakes, and currently occupy Loon Lake, Otter Lake, Bass Lake
(in Benzie County), and North Barr Lake. Zebra mussels cause
complicated and not well understood cascading trophic effects
and other alterations of aquatic faunal communities. Park staff
at the Lakeshore have noticed thick blooms of Cladophora spp. algae
in the zebra mussel infested lakes. Staff at Sleeping Bear
Dunes National Lakeshore identified the need for a thorough
inventory of fishes at inland lakes and streams within park
boundaries before the zebra mussels affect fish species composition
to a great extent. Because <90% of the fishes currently
on the species list for the Lakeshore have been verified, a
survey of fishes in this Lakeshore is also a priority of the
National Park Service Great Lakes Network Office. Further,
some studies have shown that fish species change their diet
from plankton to benthic organisms after the establishment
of zebra mussels. Because bottom sediments often harbor high
levels of toxicants and zebra mussels are known to deposit
concentrated organic pollutants in their pseudofeces, it is
possible that benthic dwelling organisms in these lakes contain
high levels of organic pollutants. To determine whether the
diets of game fishes are rich in benthic organisms it is necessary
to analyze gut contents. To determine whether game fishes have
accumulated elevated or dangerous levels of toxicants it is
necessary to analyze for contaminants.
Objectives To collect fish community information including
presence/absence, relative abundance, species richness and
diversity, stomach contents, contaminant, and size and age
class data in the streams and inland lakes of Sleeping Bear
Dunes National Lakeshore.
Project Status: Completed Final Report |
