We constructed a linkage map for cisco (Coregonus artedi), an economically and culturally important fish in the Great Lakes and across North America, which previously lacked a high-density haploid linkage map. We used diploid and haploid cisco from northern Lake Huron...
Lake Michigan
Are cisco and lake whitefish competitors in the Great Lakes? Implications for future reintroduction efforts
The overall objective of this project was to evaluate historical commercial gill net fishery data available for State of Michigan waters of Lakes Superior, Michigan, and Huron for evidence of potential negative interactions between Cisco Coregonus artedi and Lake...
Dedicated surveys to describe the distribution and abundance of a remnant cisco population in Green Bay
Contemporary spawning of cisco and lake whitefish is not known to occur in southern Green Bay but in recent years a small number (< 10 per year) of cisco adults have been recovered along the Door Peninsula, and lake whitefish larvae have been captured in drift...
Historical and contemporary genetic diversity of Coregonus species from Lake Michigan
Advancements in molecular biology methods have allowed researchers to analyze genetic variation in extinct or extirpated species where minuscule amounts of cellular material remain. Here for the first time, we have leveraged one of these methods -...
Historical habitat use by Coregonus artedi in the upper Great Lakes and critical embayments
The restoration of the once abundant cisco (Coregonus artedi) is a management interest across the Laurentian Great Lakes. To inform restoration, we describe historical distributions of cisco in the upper Great Lakes (i.e., Lakes Superior, Michigan, and Huron) by...
Building molecular tools for coregonine species identification
The larval phase of Coregonus spp. represent a bottleneck in year class strength that is not well understood in extant populations and could present an impediment for coregonine restoration efforts in the Great Lakes. The use of species-specific DNA sequences to...
Are there differences in larval and juvenile gene expression between hatchery and wild coregonids?
Management agencies are investigating best practices for coregonid (C. artedi and C. hoyi) culture, stocking, and broodstock development. However, before large scale production can begin, decisions about the sources of broodstock, culture practices, and stocking rates...
Genetic diversity among Great Lakes cisco species: exploring taxonomic and population boundaries
Ciscoes (Coregonus artedi, hoyi, kiyi, zenithicus, and nigripinnis) once formed a diverse species flock in the Great Lakes. While several taxa appear to have been extirpated, those that remain are an important part of the Great Lakes food web. Deepwater forms (C....
How does ecological function correspond to morphology in Great Lakes coregonines?
Human activities have caused widespread biodiversity loss, particularly in freshwater systems. For example, historical fish assemblages of the deepwater habitats of the Laurentian Great Lakes were dominated by up to eight closely related taxa from the genus Coregonus....
Site fidelity, depth-habitat use, and reproductive behavior of ciscoes in Grand Traverse Bay, Lake Michigan
Successful reintroduction of cisco (Coregonus artedi) to the Great Lakes requires that stocked individuals are suitably adapted to environmental conditions at stocking sites. Thus, understanding how cisco ecology, life history, and behavior varies among extant...
Comparing genetic population structure of Great Lakes cisco and lake whitefish to help determine restoration targets
Species diversity is necessary for the maintenance of sustainable fisheries because differential use of habitats can help buffer against unpredictable conditions. Therefore, an important first step to maintaining or restoring species diversity is describing extant...
Redesigning nearshore and offshore fish community protocols to incorporate new species identification approaches and determine optimal sampling strategies
The objective of this work was to begin the process of describing Lake Superior larval ciscoe population dynamics at the species level, something which was not possible prior to 2019 (Ackiss et al. 2020) and use this information to develop standard collection protocols. From 2014-2023, larval fish were sampled at 163 and collected at 159 locations across Lake Superior. Due to COVID restrictions, no sampling occurred in 2020 and sampling in 2021 was limited to USA waters. Across all years, this sampling yielded 90,618 ciscoe larvae of which 11,751 individuals were identified based on genomics. The 4,369 larval ciscoes collected in 2023 have not yet but will be genomically identified. Genomic identifications yielded 78 Bloater, 8,671 Cisco, 75 Lake Whitefish, 1,969 Kiyi, and 958 putative hybrids. Principal findings include the widespread distribution of all species across the lake by July; high annual variation in hatching dates, sequential species hatch dates that match chronological spawning periods; Cisco first, Kiyi second, and Bloater third, and the occurrence of a genetically unique stock of Cisco along the north shore of the lake.
In 2022, unprecedented larval ciscoe survival past July provided an opportunity to collect young age-0 ciscoes in August, September, and October and evaluate their population dynamics. This effort resulted in the collection and genomic identification of 79 Bloater, 456 Cisco, 1,086 Kiyi, and 77 putative hybrids. A principal finding to date was documenting the late-summer movement of these fish from the surface, their preferred habitat in May-July, to 10-15 m below the surface in early August at around 25 mm in total length. This discovery has implications for when and how these fish can be collected.
A third outgrowth of this study was the opportunity to compare morphological-based species identifications to genomic-based species identifications for age-0 and near age-1 fish. This work could lead to a better understanding of which species, and at which size they can be reliably identified aboard the ship based on morphological characteristics. Dual identifications to date include 503 Bloater, 81 Cisco, 75 Kiyi, 3 Shortnose Cisco, 4 Pygmy Whitefish, and 89 putative hybrids, with an additional 2,292 age-1 ciscoes collected in 2023 remaining to be genomically identified. Preliminary analyses show rates of accurate morphological identification as compared to genomics to be highest for Cisco and lowest for Bloater, with the overall identification accuracy exceeding 90% for all three ciscoes when total length exceeds 140 mm.