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In the summer of 2016, a population of Lepomis peltastes (Northern Sunfish), a New York State threatened species, was discovered in an 8-km reach of the Great Chazy River in Clinton County, NY. This population is the first known from the Lake Champlain watershed. Further investigation showed the population extending upstream of the lowest fish barrier for 2.3 km. Northern Sunfish were found in sheltered habitat shared with several other species of Centrarchidae. While a variety of methods were successfully used to catch Northern Sunfish, backpack electroshockers were the most effective. The future of the Northern Sunfish in New York is discussed, as well as the ecological implications for some of the other fish species in the river.

Legacies of ancient riverine systems are often manifest in patterns of genetic diversity within aquatic species. The ancient Teays River, a principal drainage of the eastern United States, engaged ...

Aim Rare aquatic species are a substantial component of biodiversity, and their conservation is a major objective of many management plans. However, they are difficult to assess, and their optimal habitats are often poorly known. Methods to effectively predict the likely locations of suitable rare aquatic species habitats are needed. We combine two modelling approaches to predict occurrence and general abundance of several rare fish species. Location Allegheny watershed of western New York State (USA) Methods Our method used two empirical neural network modelling approaches (species specific and assemblage based) to predict stream-by-stream occurrence and general abundance of rare darters, based on broad-scale habitat conditions. Species-specific models were developed for longhead darter (Percina macrocephala), spotted darter (Etheostoma maculatum) and variegate darter (Etheostoma variatum) in the Allegheny drainage. An additional model predicted the type of rare darter-containing assemblage expected in each stream reach. Predictions from both models were then combined inclusively and exclusively and compared with additional independent data. Results Example rare darter predictions demonstrate the method's effectiveness. Models performed well (R2 ≥ 0.79), identified where suitable darter habitat was most likely to occur, and predictions matched well to those of collection sites. Additional independent data showed that the most conservative (exclusive) model slightly underestimated the distributions of these rare darters or predictions were displaced by one stream reach, suggesting that new darter habitat types were detected in the later collections. Main conclusions Broad-scale habitat variables can be used to effectively identify rare species' habitats. Combining species-specific and assemblage-based models enhances our ability to make use of the sparse data on rare species and to identify habitat units most likely and least likely to support those species. This hybrid approach may assist managers with the prioritization of habitats to be examined or conserved for rare species.

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Community response to environmental gradients operating at hierarchical scales was assessed in studies of benthic diatoms, macroinvertebrates and fish from 44 stream sites in the New York City watershed. Hierarchical cluster analysis (TWINSPAN) of diatoms and fish partitioned the study sites into four groups, i.e., acid streams, reservoir outlets and wetland streams, large eutrophic streams, and small eutrophic streams; macroinvertebrate TWINSPAN distinguished an additional group of silty eutrophic streams. The correspondence among the three assemblage TWINSPAN groupings was moderate, ranging from 51 to 57%. The similarity across the four major group types was the highest among large eutrophic stream and acid stream assemblages, and the lowest among small eutrophic stream assemblages. Stepwise discriminant function analysis revealed that environmental factors discriminated most effectively the diatom grouping and least effectively the fish grouping. The best environmental predictors for diatom and macroinvertebrate grouping were conductance and percent surface water, while population density was most powerful in separating the fish groups. Carbaryl was the only pesticide that correlated with macroinvertebrate grouping. Partial redundancy analyses suggested a differential dependence of freshwater communities on the scale of the environmental factors to which they respond. The role of small-scale habitat and habitatland cover/land use interaction steadily increased across the diatom, macroinvertebrate, and fish assemblages, whereas the effect of large-scale land cover/land use declined.

Pugnose shiner (Notropis anogenus) and blackchin shiner (N. heterodon) are classified as endangered and of special concern, respectively, in New York and were thought to be rare in the Thousand Islands area of the St. Lawrence River. Both species were caught in 1993–1995, at historic Thousand Islands collections sites (in 1931 and 1983) and at new locations. Blackchin shiner occurred in 11 of 50 samples and pugnose shiner in 4 of 50 in 1993–94. In 1995, sampling extended 93 km downstream and neither species were collected there. When blackchin shiner were collected, there was a high probability of also catching pugnose shiner (regression coefficient of P=0.006). Other species commonly associated with these included tessellated darter, bluntnose minnow, banded killifish and bluegill. The population status for pugnose and blackchin shiners seems unchanged in the Thousand Islands area since the 1930's. The downstream area to Massena, Middle Corridor and Lake St. Lawrence, had no pugnose shiners and ...

Historic and contemporary records of lake sturgeon ( Acipenser fulvescens ) occurrences in new York State have been assembled in this report to assist in planning and prioritizing the areas for restoration. This has become important because information about this threatened species is not easily assembled nor easily retrieved from the few remaining fishermen. Lake sturgeon were identified in 17 waters of New York State in the Great Lakes drainage including Lakes Erie, Ontario, Champlain, and the Niagara and St. Lawrence rivers. Two other rivers in the Laurentain Great Lakes drainage had self-sustaining populations, five others historically supported spawning runs, and five other waters had historical records of use or relict populations. Lake Erie provided the largest historic fishery for lake sturgeon in New York State (1,678 tonne reported in 1885) followed by Lake Ontario (292 tonne reported in 1890). All the major waters (the first five identified above) had large harvests, and two tributaries to the St. Lawrence River, the Grasse and Oswegatchie rivers, also provided commercial harvests. The Great Lakes fisheries were reduced to abandonment by the 1940s and the remaining ones were discontinued by the 1960s. Currently, lake sturgeon are self-sustaining at very low levels in the upper Niagara, St. Lawrence, and the Grasse rivers. The fish is protected from harvest in all areas but one.

Investigation of the Hudson River Estuary largemouth bass (Micropterus salmoides) fishery began in 1984 to determine the importance of five suspected wintering areas. Tournament fishing in 1985–88 extended over 166 km of the estuary and provided recaptures of largemouth bass which were previously marked after being electrofished from winter refugia. The river-wide abundance estimate (+ 95% CI) included 29,500 ± 10,250 bass ≥305 mm for the fall and spring 1987–88, and abundance in the two prior years appeared similar. Largemouth bass abundance estimates in the winter refugia (from electrofishing recaptures) totaled 17,300 fish 2305 mm, in 1987–88. Thus, a large percentage, about 59%, of the largemouth bass in the river fishery appeared to use these five wintering refugia.

The Allegheny River drainage in southwestern New York sup- ports a diverse fish fauna that includes reports of 95 species. Of these, nine species are classified as endangered, threatened, or of special concern in New York; this number represents 38% of the listed species in the state. Thirteen of the 95 species are reported only from the Allegheny River drainage and have not been found in other New York drainages. Eleven species are introduced, and four may have migrated into the drainage recently. Individual waters with high species richness, 46-67 species, include the Allegheny River, French Creek, Olean Creek, and Chautauqua Lake. The ichthyofauna of the Allegheny River drainage is important because of the number of rare fish species present in the drainage (26) when compared to other New York drainages.

Paddlefish fisheries in some states have become increasingly important, but in other states populations have declined severely and the species range has been reduced. Commercial paddlefish harvests today come mainly from the impounded Tennessee, Mississippi, and Arkansas Rivers. Sport fisheries have replaced commercial fisheries in some areas and even though they are extremely localized, they account for sizable harvests. Declining paddlefish populations reported in several states are a result of loss of spawning habitat. Recent studies in these and other states have increased our knowledge about the paddlefish and its management. Identification and protection of spawning areas is critical to the maintenance of the fisheries.

The white catfish (Ictalurus catus) was studied in the upper Hudson River Estuary to describe its growth and habits at the northern edge of its range. Ages from pectoral spine examination showed annuli formed before June and the fish reach size of maturity after age three. Length at age was back calculated with a correction factor and by direct proportion; differences averaged only 4 mm and the correction method was favored. Spawning apparently occurred in June and July in sandy shoals and rock piles. Preferred habitats for catfish in other seasons were channel border or shoal and vegetated backwaters. Tag returns suggested a large population and indicated seasonal movements typical of this species.

Scaphirhynchus albus and S. platorynchus were studied in Missouri during 1978–1979 to assess their distribution and abundance, to obtain information on their life histories, and to identify existing or potential threats to their survival. S. platorynchus was collected in substantial numbers (4355 specimens) at all 12 sampling stations in the Missouri and Mississippi rivers, while only 11 S. albus were captured from 6 stations. Twelve specimens identified in the field as hybrids between the two species were captured from 4 stations. Morphometric and meristic comparisons of presumed hybrids with the parent species, using cluster and principal components analyses, demonstrated intermediacy of most specimens identified in the field as hybrids. Aquatic insects comprised most of the diet of S. platorynchus and S. albus, but S. albus and the hybrids had consumed considerable quantities of fish. S. albus grew more rapidly than S. platorynchus, while the growth of hybrids was intermediate. Hybridization appears to be a recent phenomenon, resulting from man-caused changes in the big-river environment. Hybridization may be a threat to survival of S. albus in the study streams.

Shading of the mound surfaces of a series of Pogonomyrmex badius colonies caused an increase in the number of migrations to new colony sites. Only 18% of the control colonies moved, while all of the shaded colonies moved at least once. The shading caused a reduction in soil temperature to a depth of 50 cm. It is speculated that the reduction in soil temperature interfered with the normal development of the brood and the colonies' response was migration to a new site. Since it invokes a predictable response, shading may be an excellent tool for future experimental studies into the behavior of P. badius. See full-text article at JSTOR

The role of zooplankton in a salt marsh ecosystem was studied in Flax Pond, Old Field, N. Y., a 30-hectare tidal pond adjacent to Long Island Sound. Various marine crustaceans accounted for over 95% of the zooplankton caloric biomass in all but three months, in which ctenophores (Mnemiopsis leidyi) accounted for about 20%. Mass balance analysis of crustacean biomass showed a seasonal trend with increased “consumption” by the marsh from July to November. Analysis of groups (or species) for all months showed total numbers were reduced by passing through, or interacting with, the marsh. The most abundant group for each sample date also was significantly reduced from outflowing waters for all months, as were the group copepodids and miscellaneous calanoids from July to November. The energy requirements for the crustacean zooplankton community could have been supplied amply by the estimated standing crop of phytoplankton in the marsh. Phytoplankton net primary production was low, but it was ample to satisfy crustacean energy needs in all months. Crustaceans and phytoplankton alone were not enough to support estimated ctenophore nutrition requirements in summer. Therefore, detritus may also have been an important ctenophore food source.