TITLE: Rapid Assessment of LakeSturgeon Spawning Stocks Using Fixed-location, Split-beam Sonar Technology
PI: Nancy Auer
Co-PIs:Partner(s): Dr. Ed Baker, Department of Natural Resources
Sponsor:Great Lakes Fishery Trust
Award Amount: $268,338
Project Duration: 2002-2005
MTU Proposal/Project Nbr: 010327
Link to Project Website:
Abstract
Fixed-location, split-beam sonar technology was used successfully to identify adult lake sturgeon as they moved upstream and downstream for spawning in the Sturgeon River, Michigan May – June 2004. We used a Hydroacoustic Technology Inc. model 241 split-beam echo-sounder operating at 200 kHz and a single 4.0 x 10º elliptical-beam transducer with a near field range of 0.1 m set perpendicular to the river flow. Data collected from migrating lake sturgeon included, swimming speed, range from transducer, time and date of passage, and target strength. The spawning population of lake sturgeon was estimated to be at 350 – 400 fish with almost equal numbers of fish being seen moving upstream as downstream. Most fish were recorded moving within the mid-section of the river, 1.5 – 1.65 m deep, and swimming speeds upstream were slower than those for downstream moving fish. Our results show that spilt-beam sonar can be applied to lake sturgeon assessments, without the stress of actually handling these large,pre-spawning fish.
Project Highlights
(Conference presentations, publications, awards, notable results)
Auer, N.A. and E. A. Baker (in review) Rapid Assessment of LakeSturgeon Spawning Stocks Using Fixed-location, Split-beam Sonar Technology.
Will be presented at the 136th Annual Meeting of the American Fisheries Society, Lake Placid, New York, September 10-14 2006.
TITLE: Comparative performance in early-life history of streamside-reared and wild-reared
lake sturgeon in the ManisteeRiver.
PI: Nancy Auer
Co-PIs:
Partner(s): Marty Holtgren, Fishery Biologist, Little River Band of Ottawa Indians
Sponsor: Great Lakes Fishery Trust
Award Amount: $83,893
Project Duration: 2005-2007
MTU Proposal/Project Nbr: 040717
Link to Project Website:
Abstract
Fishery managers are seeking techniques to rehabilitate sturgeon stocks by increasing reproductive success while maintaining natural population performance attributes. Knowledge gaps exist in evaluating methods for rehabilitating remnant stocks, especially considering performance differences between wild and reared fish of similar genetic makeup. This study will evaluate a streamside-rearing program in rehabilitating remnant sturgeon stocks by comparing growth, habitat use, movement, and parental contribution of reared sturgeon to wild.
Lake sturgeon rehabilitation is currently a focus of many Great Lakes agencies. Intervention strategies are a management focus sincemost lake sturgeon populations are extremely small and believed to be at <1% of their historic abundance. A primary impediment to sturgeon rehabilitation is the lack of information on the effects of varying methodologies and strategies on performance and genetic attributes of the population. Currently, sturgeon managers lack critically needed information to determine appropriate methodologies for repatriation of remnant or extirpated stocks. The benefit of remnant stock rehabilitation is that it provides an opportunity to use existing fish as broodstock. Stocking usually takes place in a traditional manner where gametes are collected, hatched and reared at a hatchery, and returned back to the natal source. However, at the Great Lakes Lake Sturgeon Coordination Meeting held 11-12 December 2002 there was concern expressed about straying and spawning site fidelity associated with this practice. Though stocking is a standard management tool it is only one of many options available. Effectiveness of other intervention techniques needs to be thoroughly investigated. Recently, the Little River Band of Ottawa Indians (LRBOI) designed and constructed a Streamside Rearing Facility (SRF) for larval and young-of-yearlake sturgeon. This approach is unique from traditional stocking practices in that larvae will be collected and reared within their natal water source with natural temperature regimes. This technique needs to be evaluated to determine if it presents an appropriate rehabilitation option, and maintains appropriate performance and genetic attributes of the population.
Project Highlights
(Conference presentations, publications, awards, notable results)
TITLE:Status Assessment of RemnantLake Sturgeon Stocks in the Lake MichiganBasin
PI: Nancy Auer
Co-PIs:
Partner(s): Dr. Ed. Baker, Michigan Department of Natural Resources
Sponsor: U.S. Fish and Wildlife Service
Award Amount: $120,783 + 70,707
Project Duration: 2001-2006
MTU Proposal/Project Nbr: 010827 + 040647
Link to Project Website:
Abstract
Biologists and researchers from throughout the region are continuing collaborative efforts to determine the current status and rehabilitation needs of remnant lake sturgeon populations in Lake Michigan. Historically, sturgeon were abundant in Lake Michigan and reproduced in many rivers. Populations declined rapidly in the late 1800s due to habitat loss, degraded water quality, and overfishing. Knowledge of current sturgeon distribution, abundance, and reproduction is critical to furthering conservation and rehabilitation efforts for the species.
We propose to continue for one final field season, basin-wide investigations begun in 2001 to assess the current status of remnant lake sturgeon populations or stocks in Lake Michigan. This project will focus and expand our current status assessment efforts to additional waters showing promise of containing persistent populations of lake sturgeon but where previous effort and data are limited (Cedar, Manistique and Kalamazoo rivers, and Little Traverse Bay). Additional focus also will be given to three rivers having longer assessment histories but for which additional information is critical for determining appropriate management or rehabilitation actions (Menominee, Manistee and Muskegon rivers). Both the Manistee and Muskegon rivers support the presumed largest remaining populations in lower Michigan tributaries, but both are small and likely vulnerable. The Menominee River supports the presumed largest sturgeon population in Lake Michigan but population abundance is not well established and harvest rates and populations effects of a fall hook and line harvest fishery in this system are unknown. Methods will be employed in each system that have been standardized, refined, and found to be most successful for the target study areas based on previous years work. This project brings the combined effort of 9 co-principal investigators working on 7 coordinated subprojects. Specific subproject design and methods are described in more detail below under each subproject.
Project Highlights
(Conference presentations, publications, awards, notable results)
Lepera, F.A. 2004 Adult lake sturgeon (Acipenser fulvescens) assessment in northern Lake Michigan and pre-spawning microhabitat in the Upper peninsula of Michigan. A report submitted in partial fulfillment of the requirements for the degree of Master of Science in Biological Sciences.
TITLE: KITES/Biological Communities: BENTHOS AND LARVAL FISH COMMUNITIES
IN: Impact of the Keweenaw current on cross-margin transport in Lake Superior
PI: Sarah Green
Co-PIs: Nancy Auer, Noel Urban, Charlie Kerfoot, Marty Auer, Judy Budd.
Partner(s):
Sponsor: National Science Foundation 5.4 million
Award Amount: $362,880 (N. Auer portion)
Project Duration: 1997-2004
MTU Proposal/Project Nbr: 970312
Link to Project Website:
Abstract
The objective of the field and laboratory measurements is to quantify gradients in composition and rate of production of inshore/offshore benthos and fish communities and to identify and quantify the critical factors controlling ecosystem dynamics in Lake Superior and provide data to constrain and test the coupled biological - physical model.
Students - Jason Oyadomari (Ph.D.) and Gene Mensch (MS) Jason Kahn (MS).
Larval Fish Community Hypothesis:
The Keweenaw Current acts as a significant barrier to the distribution and migration of larval fish, keeping pelagic species offshore and nearshore and tributary-produced larvae confined to nearshore regions. The Keweenaw Current also forces distribution of larvae out to the tip of the Keweenaw Peninsula.
Benthos Community Hypothesis:
Nearshore/offshore gradients in temperature, bacterial production, and sediment composition determine the distribution of benthic organisms along the Keweenaw peninsula and these distributions are coupled with nearshore and tributary sediment and nutrient loadings.
Objectives:
1) Sample larval fish distribution during early spring and thermal bar formation to determine patterns in abundance for pelagic species such as lake herring.
2) Sample larval fish distribution nearshore and resulting from tributary inputs to determine patterns in abundance for nearshore species such as white sucker.
3) Sample larval fishes along the Keweenaw Current from south to north to determine if larval fish are being carried along the current.
4) Sample for benthic organisms along each transect to identify community composition, and connections with bacterial, sediment and nutrient distribution.
Project Highlights
(Conference presentations, publications, awards, notable results)
Oyadomari, J.K. and N.A. Auer. 2004. Inshore-Offshore distribution of larval fishes in Lake Superior off the western coast of the Keweenaw Peninsula, Michigan. Journal of Great Lakes Research. Vol. 30, Supplement 1, 369-384.
Auer, N.A. and J.E. Kahn. 2004. Abundance and distribution of benthic invertebrates, with emphasis on Diporeia, along the Keweenaw Peninsula, Lake Superior. Journal of Great Lakes Research, Vol. 30, Supplement 1, 340-359.
Mensch H.E. 2001. Dispersal and Distribution of ichthyoplankton within Eagle River, Michigan and adjacent coastal waters of lake Superior. An MS thesis, Dept. Biol. Scis., Mich. Tech. Univ.