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Neil H. Ringler

Publications and source records attributed to Neil H. Ringler.

3 recordsLinked to original sources

Mark retention of calcein in Cisco and Bloater

Since 2012, a multi-agency initiative to restore these native forage species has been under way. Evaluating the restoration success of Cisco Coregonus artedi and Bloater C. hoyi in Lake Ontario waters requires methods to identify stocked fish. However, juvenile Cisco and Bloater are fragile; thus, mass marking techniques that reduce the handling of individual fish are required and have not previously been evaluated. In 2014–2015 we evaluated the usefulness of calcein (SE-MARK) as a marker on bony structures, including the otolith. Juvenile Bloater and Cisco (14, 100, 128 d old) were immersed in a calcein bath at 5,000 mg/L of water for 4 min to apply the chemical marker. Observations of the marking retention were evaluated 8 d following the treatment. All fish immersed in calcein had strong brilliant marks (rating scale 3) on all bony structures including scales, fin rays, jaw bones, and vertebrate. The otolith was the only hard structure that did not show a brilliant marking due to the opaque nature of the structure. Our results suggest that calcein produces a strong discernable mark on hard bony structures of Cisco and Bloater; however, long-term retention needs further study.

Lake Ontario↗

Comparative diets of subyearling Atlantic salmon and subyearling coho salmon in Lake Ontario tributaries

Restoration of Atlantic salmon ( Salmo salar ) in Lake Ontario could potentially be negatively affected by the presence of non-native salmonids that are naturalized in the basin. Coho salmon ( Oncorhynchus kisutch ) have been spawning successfully in Lake Ontario tributaries for over 40 years and their juveniles will reside in streams with juvenile Atlantic salmon for one year. This study sought to examine interspecific diet associations between these species, and to compare diets to the composition of the benthos and drift in three Lake Ontario tributaries. Aquatic insects, mainly ephemeropterans and chironomids were the major prey consumed by subyearling Atlantic salmon whereas terrestrial invertebrates made up only 3.7% of the diet. Ephemeropterans and chironomids were the primary aquatic taxa consumed by subyearling coho salmon but, as a group, terrestrial invertebrates (41.8%) were the major prey. In sympatry, Atlantic salmon fed more actively from the benthos whereas the diet of coho salmon was more similar to the drift. The different feeding pattern of each species resulted in low interspecific diet similarity. There is likely little competition between these species for food in Lake Ontario tributaries as juveniles.

New York↗

Influence of nearshore structure on growth and diets of yellow perch ( Perca flavescens ) and white perch ( Morone americana ) in Mexico Bay, Lake Ontario

The growth diets of 969 yellow perch ( Perca flavescens ) and white perch ( Morone americana ) caught at 3.3 and 7.0 m depths were compared between two cobble/rubble shoals and two featureless sand sites in Mexico Bay, eastern Lake Ontario during 1981. The growth rate of both species was significantly greater for individuals captured over the cobble/rubble shoals. Females of both species were faster growing than the males, although only significantly so in the white perch. The seasonal diet and breadth of diet (H′) of yellow perch and white perch were not substantially different with respect to substrate type. Diet overlap between substrate types was also equivalent for each species. Benthic invertebrates, primarily Gammarus spp., were the major prey of both species at all sites. Alewife eggs were the most important item for the white perch in mid-summer, and alewife juveniles were important to both species in the fall. Differences in growth patterns between cobble/rubble shoals and sand sites illustrate a subtle effect of habitat on these species.

Journal of Great Lakes Research↗