Northeastern Naturalist Vol. 25, No. 1 E.C. Maxwell and D.M. Carlson 2018 181 2018 NORTHEASTERN NATURALIST 25(1):181–187 The First Record of Northern Sunfish ( Lepomis peltastes) in the Lake Champlain Watershed Eric C. Maxwell1,* and Douglas M. Carlson1 Abstract - 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. Introduction Lepomis peltastes Cope (Northern Sunfish) is a relatively small sunfish native to the Great Lakes region of North America. In New York, this species was historically known from a handful of streams in the Erie-Niagara, Lake Ontario, and Oswego River watersheds (Carlson et al. 2016). This species experienced a significant decline in New York during the 20th century. The only known population that persisted in New York into the 2000s was in a 6-km segment of Tonawanda Creek in the Erie–Niagara watershed (Carlson et al. 2016). Despite a 10-year stocking program that began in 2006, Northern Sunfish have apparently been unable to persist in western New York. Northern Sunfish are also present in the Canadian provinces of Ontario and Québec, although the populations in the latter province are also declining dramatically (COSEWIC 2016). Despite this species’ historic presence just a few kilometers north of the New York–Québec border, no Northern Sunfish have ever been collected in northern New York. On 5 September 2016, a single Northern Sunfish was caught by angling over an expanse of gravel at the boat launch in the village of Champlain, NY. Between 1985 and 2015, this lower portion of the Great Chazy River was sampled by the NY State Department of Environmental Conservation (NYSDEC) 77 times, making this catch of a Northern Sunfish particularly surprising, as prior to this survey, no Northern Sunfish had been recorded from the river. The previous NYSDEC studies revealed 54 fish species living in the lower part of the river, including 3 species of sunfish: Lepomis auritus (L.) (Redbreast Sunfish), L. gibbosus (L.) (Pumpkinseed), and L. macrochirus Rafinesque (Bluegill) (NYSDEC, unpubl. data). The Northern Sunfish closely resembles the Pumpkinseed, with which it co-occurs in the Great 1NYSDEC Bureau of Fisheries, Region 6, Watertown, NY 13601. *Corresponding author - eric.c.maxwell@gmail.com. Manuscript Editor: Joseph Rachlin Northeastern Naturalist 182 E.C. Maxwell and D.M. Carlson 2018 Vol. 25, No. 1 Chazy River, and it is possible that specimens of this species have been collected in the river before but were mistaken for the more common Pumpkinseed. The Northern Sunfish can be distinguished from Pumpkinseed by the former’s stouter form; short, rounded pectoral fins; and orange membranes on the dorsal and anal fins (Smith 1985). Northern Sunfish also have fewer, larger lateral-line scales than Pumpkinseed: 34–38 and 38–43, respectively (Becker 1983). Specimens were archived at New York State Museum (no. 74853). The nearest New York record of a Northern Sunfish is from 241 km away in the outlet of Oneida Lake, where the species has apparently not been seen since the 1940s (Carlson e t al. 2016). Study Area The Great Chazy River is one of the northernmost rivers in the Lake Champlain basin, entering the lake about 10 km south of Québec (Fig. 1). The river drains 787 km2 of northeastern New York and a small part of adjacent Québec. This study was conducted along the lowest 15.6 km of the river downstream of Perry Mills, which has a typical lowland topography contrasting with the Adirondack Mountain landscape in the upper half of the sub-basin. The river is generally a rocky and sandy stream until it reaches Route 11 below Champlain, at river kilometer (rkm) 7.6. At this point, the river becomes wider, deeper, and more turbid, with the substrate dominated by clay and fine silt. Aquatic vegetation, including Elodea (waterweed), Figure 1. Location of sample sites on the Great Chazy River . Northeastern Naturalist Vol. 25, No. 1 E.C. Maxwell and D.M. Carlson 2018 183 Vallisneria (eel grass), and Potamogeton spp. (pondweeds), is found in shallow, quiet portions of the river throughout this nearly 16-km reach. Vegetation is especially abundant near the mouth of the river at depths of less than 1 m. The first shallow area with an extensive riffle is found in the village of Champlain at rkm 8.2. There is 1 barrier in the study area, at rkm 12.9, called Whiteside Dam (also known as Frog Farm Pond Dam). This was an historic mill dam which has been upgraded to impede Petromyzon marinus L. (Sea Lamprey). It functions as a barrier to all or nearly all upstream fish movement and creates wider, lake-like conditions upstream for about 3 km. The next sample site was at the upper end of this impounded reach and just downstream of Perry Mills. The section below Perry Mills is shallow and rocky, with occasional pools and runs with sparse vegetation. Methods During September 2016, we made 3 trips to the Great Chazy River, with the first resulting in the unexpected catch using an artificial bead-head nymph on a hook with a gap of ~3 mm. Five sites (Fig. 1) were chosen later in September based on accessibility and maximizing habitat diversity, with 1 site chosen for stream-like habitat upstream of the lowest fish barrier at rkm 12.9 (Fig. 1). To maximize effective sampling efforts, we used a combination of fly fishing, seining, backpack electrofishing, and boat electrofishing. A 15.24 m x 1.22 m (50 ft x 4 ft) bag seine with 6.35-mm (¼-in) mesh was deployed at 2 sites, and a 9.14 m x 1.22 m (30 ft x 4 ft) bag seine with 6.35-mm mesh and a bag with 3.18-mm (⅛-in) mesh was used at 2 others. At 4 of the 5 sites, we employed backpack electrofishing using 2 battery-powered units: an ETS electrofishing systems model ABP-3 and a Smith- Root model 12. During the final trip, we employed boat electrofishing in deeper water, with a Smith-Root Type VI-A boat electrofisher at the 3 most downstream sites (Fig. 1). Results All gear provided catches of Northern Sunfish. The most effective sampling gear were the backpack electroshockers, which caught 12 of the 19 total Northern Sunfish. The least effective sampling gear were the seines and fly fishing, which only caught 1 Northern Sunfish each. Boat electrofishing caught the remaining 5 individuals. Northern Sunfish were caught at all sites above Route 11 in the village of Champlain (Fig. 1). Sizes were typical of adult Northern Sunfish in New York and varied from 58 mm to 91 mm. In the areas downstream of Whiteside Dam, Northern Sunfish were generally collected alongside Bluegill and Pumpkinseed. All of the individuals found at Perry Mills were found in an extremely localized part of the stream at the upper end of the impoundment from Whiteside Dam. The small pocket of quiet water where they were caught had a dense growth of Elodea, and had also accumulated some leaf litter and other woody debris. Aside from the Northern Sunfish, the only Centrarchids present in this vegetation were a single Pomoxis nigromaculatus (Lesueur) (Black Crappie) and numerous juvenile Ambloplites rupestris Northeastern Naturalist 184 E.C. Maxwell and D.M. Carlson 2018 Vol. 25, No. 1 (Rafinesque) (Rock Bass). This was the only site where young-of-year (33–38 mm) Northern Sunfish were caught. Discussion The recent discovery of an apparently healthy population of Northern Sunfish in New York is encouraging for the species’ long-term survival prospects in the state and across its range. This population is on the extreme northeastern edge of its range, and nearby populations in Québec are in dramatic decline: no Northern Sunfish have been seen east of the mouth of the Châteauguay River near Montreal since one was caught there in 2005, which was itself the first record of this species in the province since at least 1994 (COSEWIC 2016). This species is apparently intolerant of siltation and turbidity, and extensive agricultural development in Québec has undoubtedly been a significant contributor to their disappearance: 72% of Québec’s Châteauguay River watershed is agricultural land (COSEWIC 2016, Simoneau 2007). It is classified as a species of special concern in Canada. The Great Chazy River population may prove to be an important refuge population for future recovery efforts in this part of their range. The reason for this species’ apparently sudden appearance in the river after several decades of sampling is unclear. Their superficial similarity to Pumpkinseed, especially at small sizes, may have caused them to be overlooked by previous investigators. It could also be that recent improvements in the quality of their habitat have caused this population to increase to detectable levels, or that this population of Northern Sunfish is only vulnerable to sampling at certain times of the year or during special water conditions. In May of 2017, we resampled in the same area to determine if Northern Sunfish could still be caught. Despite unfavorable sampling conditions due to recent heavy rains, several yearling Northern Sunfish were collected, indicating that they are likely present in this part of the river year-round. The threat of invasive species The increasing threat of invasive species is a cause for concern throughout this species’ range. Neogobius melanostomus (Pallas) (Round Gobies) were first reported in western New York in ca. 1995 (Fuller et al. 2017), and are now a dominant part of the fish fauna in western New York streams that historically supported Northern Sunfish (Sanderson-Kilchenstein 2015). Their aggressive behavior and nocturnal activity are presumed to allow the Round Gobies to intimidate or outcompete Northern Sunfish. Although gobies have now spread throughout Lake Ontario and the St. Lawrence River, they have not yet arrived in the Lake Champlain basin. Round Gobies are expected to eventually reach the Lake Champlain basin via the Richelieu River and/or the Hudson-Champlain Canal. Despite their extraordinary dispersal capability, this species is unlikely to be able to naturally surmount barriers such as Whiteside Dam. A second invasive species that has likely had a great effect on western New York fish communities, and that is not yet in the Champlain basin, is Lepomis cyanellus Northeastern Naturalist Vol. 25, No. 1 E.C. Maxwell and D.M. Carlson 2018 185 Rafinesque (Green Sunfish). This species is native to Lake Erie and the Midwest’s Mississippi drainage, but has been introduced into many other areas throughout the country and can now be found in all New York watersheds except Champlain, Upper Hudson, and Oswegatchie (Carlson et al. 2016). They are now the dominant sunfish in Tonawanda Creek, which held the last known population of Northern Sunfish in western New York. Like the Round Goby, their aggressive behavior is presumed to intimidate and outcompete the smaller and less aggressive Northern Sunfish when they co-occur in Tonawanda Creek (Sanderson-Kilchenstein 2015). This relationship, however, has not been confirmed where the 2 species co-occur in the Midwest. This species could eventually make its way into Lake Champlain and its tributaries via the same pathways as the Round Goby . In the Great Chazy River, a relatively new invasive species was discovered in this study. We observed schools of >50 Scardinius erythrophthalmus (L.) (Rudd), especially near the mouth of the river and at rkm 2.2. This large Eurasian minnow is remarkably similar in appearance and behavior to the native Notemigonus crysoleucas (Mitchill) (Golden Shiner). Rudd have been reported from Lake Champlain since 1991 (Marsden and Hauser 2009), but never from the Great Chazy River. An extensive review of the species’ distribution in the basin remains to be performed. It is assumed to have been introduced via bait-bucket release. The effect of Rudd on native species is currently unknown, but due to its large maximum size and high reproductive output, it has the potential to become disruptive to other species. Their high abundance and habit of consuming macrophytes caused concern in western New York (Kapuscinski et al. 2012). The species is no longer offered at bait stores in New York, but it has apparently already become established in several watersheds. Although there is a growing consensus that stream impoundments negatively impact native fish populations, an argument could be made that some of the existing dams in this part of the state have been beneficial to the long-term survival prospects of Northern Sunfish and other native species. As several invasive species are already present in the river below Whiteside Dam but not above it, it seems likely that the dam affords a level of protection from invasive species. This consideration is especially relevant in the case of Round Goby and Green Sunfish, 2 invasive species in New York that could appear in the Lake Champlain basin and which are already implicated in the disappearance of Northern Sunfish from their historic strongholds in western New York. Recommendations Measures to protect the habitat required by this threatened species should be implemented. The species richness of this area is uncommonly high for Champlain tributaries, and monitoring should continue to see if other sensitive species might have returned or could possibly be detected for the first time. Such species include Percina copelandi (Jordan) (Channel Darter), which hasn’t been caught in the Great Chazy River since 1927 but is experiencing range expansion to the south, and Ammocrypta pellucida (Putnam) (Eastern Sand Darter), which is extending its range north in Lake Champlain tributaries (Carlson et al. 2016) . Northeastern Naturalist 186 E.C. Maxwell and D.M. Carlson 2018 Vol. 25, No. 1 Despite the fact that the Northern Sunfish appears to be persisting without human intervention in the Great Chazy River, it is apparent that this population may prove critical to the long-term survival of this species in New York State. Thus, steps should be taken to ensure that the habitat in the area is not negatively impacted by agricultural runoff including cow manure, which is regularly applied to row crops in this area and can result in fish kills when accidental spills occur (Meade 2004). Whiteside Dam, perhaps the only barrier preventing non-native species from invading the upstream segment of the Northern Sunfish habitat, should definitely be maintained as a fish barrier for the foreseeable future. It not only keeps Sea Lamprey away from their potential spawning areas but also keeps out other non-native species. Due to the Northern Sunfish’s small size, it is not likely to be at risk from overfishing in the Great Chazy River. However, signage could be posted at the few fishing access sites in the area to educate anglers on proper identification of this rare species and advise them not to harvest any that might be caught . In addition to documenting the distribution of Northern Sunfish beyond the lowest 16 km of the Great Chazy River, future efforts should attempt to determine the total extent of their range in this river and nearby areas. Acknowledgments We thank David Sanderson-Kilchenstein for his extensive assistance in the field and for recognizing young-of-year specimens at Perry Mills. Russ McCullough reviewed an earlier draft of the manuscript. Literature Cited Becker, G.C. 1983. Fishes of Wisconsin. University of Wisconsin Press. Available online at: http://digital.library.wisc.edu/1711.dl/EcoNatRes.FishesWI. Accessed 27 February 2018. Carlson, D.M., R.A. Daniels, and J.J. Wright. 2016. Atlas of inland fishes of New York. New York State Museum Record 7. Avaialbe online at http://www.nysm.nysed.gov/common/ nysm/files/atlasofinlandfishes.pdf. Accessed 2 November 2017. Committee on the Status of Endangered Wildlife in Canada (COSEWIC). 2016. COSEWIC assessment and status report on the Northern Sunfish, Lepomis peltastes: Saskatchewan - Nelson River populations and the Great Lakes - Upper St. Lawrence populations, in Canada. Ottawa. xv + 51 pp. Available online at http://www.registrelep-sararegistry. gc.ca/default.asp?lang=En&n=7012C4A3-1. Accessed 31 October 2017. Fuller, P., A. Benson, E. Maynard, M. Neilson, J. Larson, and A. Fusaro. 2017. Neogobius melanostomus. USGS Nonindigenous Aquatic Species Database, Gainesville, FL. Available online at https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=713. Accessed 31 October 2017. Kapuscinski, K.L., J.M. Farrell, and M.A. Wilkinson. 2012. First record of abundant Rudd populations in North America. North American Journal Fisheries Management. 32:82–86. Marsden, J.E., and M. Hauser. 2009. Exotic species in Lake Champlain. Journal of Great Lakes Research 35:250–65. Meade, R. 2004. Fish and invertebrate recolonization in a Missouri prairie stream after an acute pollution event. North American Journal of Fisheries Management, 24:7–19. Northeastern Naturalist Vol. 25, No. 1 E.C. Maxwell and D.M. Carlson 2018 187 Sanderson-Kilchenstein, D. 2015. Aspects of Bowfin and Northern Sunfish biology and ecology. M.Sc. Thesis. SUNY Brockport, Brockport, NY. Simoneau, M. 2007. État de l’écosystème aquatique du bassin versant de la rivière Châteauguay: faits saillants 2001-2004, Québec, ministère du Développement durable, de l’Environnement et des Parcs, Direction du suivi de l’état de l’environnement, ISBN 978-2-550-50193-0 (PDF), 16 pP. Smith, C.L. 1985. Inland Fishes of New York State. New York State Department Environmental Conservation, Albany, NY. 522 pp.