PROTECTING AN UPPER HUDSON HERITAGE LAKE: ASSESSING THE NEED FOR FISH BARRIER INSTALLATION AT WOLF LAKE, NEWCOMB, NY
A Final Report of the Tibor T. Polgar Fellowship Program
Samouel J. Beguin
Polgar Fellow
Adirondack Ecological Center SUNY College of Environmental Science & Forestry Newcomb, NY 12852
Project Advisors:
Karin E. Limburg Department of Environmental and Forest Biology SUNY College of Environmental Science & Forestry Syracuse, NY 13210
Stacy A. McNulty Adirondack Ecological Center SUNY College of Environmental Science & Forestry Newcomb, NY 12852
Beguin, S.J., K.E. Limburg, and S.A. McNulty. 2018. Protecting an Upper Hudson Heritage Lake: Assessing the Need for Fish Barrier Installation at Wolf Lake, Newcomb, NY. Section VI: 1-34 pp. In D.J. Yozzo, S.H. Fernald, and H. Andreyko (eds.), Final Reports of the Tibor T. Polgar Fellowship Program, 2015. Hudson River Foundation.
VI-1 ABSTRACT
Wolf Lake, a near-pristine heritage lake, is one of the most ecologically sound
bodies of water within the Upper Hudson River headwaters region and provides a critical
aquatic reference system as well as a potential reserve for genetic diversity. The goals of
this project were to (1) describe the composition and movements of a minimally studied
stream fish community at multiple locations along the main outlet stream of Wolf Lake,
(2) determine if non-native fish species were present anywhere along the stream, and (3)
assess the need for a passive fish barrier to inhibit non-native invasion as a means of
maintaining the lake’s ecological condition. Minnow traps and visual implant elastomer
(VIE) tags were used to capture and mark fish of several species from June-August 2015.
Fish community composition varied along the length of the stream, with cutlips minnow
(Exoglossum maxillingua) found only near the outlet of Wolf Lake and non-native black
bass (Micropterus sp.) detected only at the most downstream site. Creek chub (Semotilus atromaculatus) and blacknose dace (Rhinichthys atratulus) dominated the fish community at interior stream sites downstream from Wolf Lake. Existing ephemeral barriers to fish movement along the stream included beaver wetlands, culverts, woody debris dams, and stream reaches with partial subterranean flow. The findings of this study suggest that invasion potential is low at present, although non-native species dispersal upstream remains a possibility. Further research should examine temporal patterns of fish movements in greater detail and identify more specifically the ideal locations and types of fish barriers that could be installed to prevent invasion of Wolf Lake, one of the most ecologically valuable water resources within the Upper Hudson River Watershed.
VI-2 TABLE OF CONTENTS
Abstract ...... VI-2
Table of Contents ...... VI-3
Lists of Figures and Tables ...... VI-4
Introduction ...... VI-5
Methods...... VI-11
Study Area and Sites ...... VI-11
Field Sampling ...... VI-13
Stream Barrier Assessment ...... VI-16
Data Analysis ...... VI-16
Results ...... VI-17
Water Quality ...... VI-17
Fish Capture and Distribution ...... VI-18
Fish Recaptures ...... VI-24
Stream Barriers ...... VI-24
Discussion ...... VI-26
Conclusions ...... VI-31
Acknowledgments...... VI-31
Literature Cited ...... VI-32
VI-3 LIST OF FIGURES AND TABLES
Figure 1 – Map of Wolf Lake within the Hudson River Watershed ...... VI-12
Figure 2 – Map of five study sites along the Wolf Lake outlet stream ...... VI-13
Figure 3 – Fish marked with visible implant elastomer (VIE) tags ...... VI-14
Figure 4 – Size distribution for common shiner (Luxilus cornutus) ...... VI-21
Figure 5 – Size distribution for all fish captured ...... VI-21
Table 1 – Fish species present in and absent from Wolf Lake ...... VI-7
Table 2 – Study site information for the Wolf Lake outlet stream ...... VI-13
Table 3 – Water quality measurements for study locations ...... VI-17
Table 4 – Summary of fish capture data for the Wolf Lake outlet stream ...... VI-18
Table 5 – Raw abundance for fish species captured ...... VI-19
Table 6 – Percent composition (%) for fish species captured ...... VI-20
Table 7 – Mean total length (mm) for five fish species ...... VI-22
Table 8 – Mean mass (g) for five fish species ...... VI-22
Table 9 – Summary of snorkel surveys at the Wolf Lake outlet ...... VI-23
Table 10 – Summary of fish marked using VIE tags ...... VI-24
Table 11 – List of recaptured individual fish ...... VI-25
Table 12 – Potential barriers to fish movement ...... VI-26
VI-4 INTRODUCTION
One of the most persistent threats to aquatic ecosystems is invasion by non-native species, which provoke major shifts in ecological structure and function, as a type of bio- pollution (Crait and Ben-David 2003). Furthermore, as global climate change continues, aquatic invasions may become even more pervasive in some areas (Rahel and Olden
2008). Fish invasion in particular has the potential to restructure ecological relationships within aquatic ecosystems and even influence food webs in adjacent terrestrial riparian zones (Baxter et al. 2004). In the far northern portions of the Upper Hudson River
Watershed, New York, USA, aquatic invasive plant and animal species continue to encroach on even the most protected and remote waters. Despite the land and freshwater conservation benefits provided by the Adirondack Park – a vast protected landscape of public and private lands – many lakes, ponds, streams, and rivers in the Hudson River headwaters region have experienced considerable impacts from human introduction of non-native fish species like golden shiner (Notemigonus crysoleucas), largemouth bass
(Micropterus salmoides), northern pike (Esox lucius), and smallmouth bass (Micropterus dolomieu) (APANSMP 2006; Adirondack Council 2008; Daniels et al. 2011). Yellow perch (Perca flavescens) may be considered a non-native nuisance species as well, though recent paleogenetic work suggests that this species may be native in the central
Adirondacks (Stager et al. 2015). In response to invasion, efforts are underway to
“reclaim” some Adirondack water bodies by removing introduced fish species such as smallmouth bass in order to promote the re-establishment of native species such as brook trout (Salvelinus fontinalis) (Weidel et al. 2007).
VI-5 Despite the many Upper Hudson water bodies that have already been colonized
by invasive fish species, some holdout refuges for native fish communities still remain
and allow for the maintenance of aquatic ecological integrity and genetic diversity.
One such sanctuary is Wolf Lake (also known as Wolf Pond) in Newcomb, NY. This
Adirondack water body is hydrologically connected to the Upper Hudson River and is
one of only very few waters bodies in the region that still contains an all-native heritage
fish community (Stager and Sanger 2003). Based on biological surveys, water chemistry,
and paleoecological records, Wolf Lake can be conceptualized as what Stager and Sanger
(2003) term a “heritage lake” – a water body at the least degraded end of a continuum
that ranges from water bodies that are extremely influenced by human factors to water
bodies that are all but devoid of human impacts. Though no body of water is completely
immune to global anthropogenic stressors, such as atmospheric deposition or climate change, this very rare “heritage” designation indicates that it is among the most pristine
water bodies in the Adirondack Park and likely the northeastern US (Stager and Sanger
2003).
As such, the lake’s value for aquatic research and as an extant ecological relic
cannot be overstated. Wolf Lake has avoided many of the major environmental pressures
found in other Upper Hudson aquatic systems due to its remote geographic position,
minimal disturbance history, and lack of public access. So far, the lake has avoided
invasion by non-native fishes like golden shiner and contains only the native fish species
that have likely occupied the lake for millennia (Table 1; Limburg 2002-2015, unpublished data; Stager and Sanger 2003; Schwender 1989).
VI-6 This lack of introduced fishes is notable, as many Adirondack lakes are now dominated by introduced, non-native fish species (Daniels et al. 2011). Though all lakes in the northeast experience atmospheric pollution to some degree, Wolf Lake has not acidified (pH of 6.5-7.0), holds clear water (Secchi depths 5-8 m), and supports intact diatom and algal communities. In addition, lake sediment analysis indicates conditions similar to those prior to European settlement (Stager and Sanger 2003). These findings further bolster the status of Wolf Lake as a heritage ecosystem. Because of its location on the Huntington Wildlife Forest – a biological research station and biodiversity preserve – local watershed impacts from logging, road building, and other human activities have been minimal. Recreational fishing and boating activity on Wolf Lake is strictly forbidden and therefore invasive bait species such as golden shiner have not been introduced, despite their presence elsewhere in the regional vicinity (Adirondack Council
2008).
Species Status Present? Blacknose dace (Rhinichthys atratulus) 3 Native Yes Brook trout (Salvelinus fontinalis) 2, 3 Native Yes Brown bullhead (Ameiurus nebulosus) 1, 2 Native Yes Common shiner (Luxilus cornutus) 1, 2, 3 Native Yes Creek chub (Semotilus atromaculatus) 1, 2, 3 Native Yes Cutlips minnow (Exoglossum maxillingua) 1, 2, 3 Native Yes Northern redbelly dace (Chrosomus eos) 1, 2, 3 Native Yes Pumpkinseed sunfish (Lepomis gibbosus) 1, 3 Native Yes Redbreast sunfish (Lepomis auritus) 1, 2, 3 Native Yes Slimy sculpin (Cottus cognatus) 3 Native Yes White sucker (Catostomus commersonii) 1, 2, 3 Native Yes Golden shiner (Notemigonus crysoleucas) 1, 2, 3 Non-native No Largemouth bass (Micropterus salmoides) 1, 2, 3 Non-native No Northern pike (Esox lucius) 1, 2, 3 Non-native No Smallmouth bass (Micropterus dolomieu) 1, 2, 3 Non-native No 1 Limburg 2002-2015, unpublished data 2 Stager and Sanger 2003 3 Schwender 1989
Table 1. Fish species present in and absent from Wolf Lake, Newcomb, NY, USA.
VI-7 Wolf Lake remains one of most pristine aquatic systems in the entire Hudson
River Basin, but its long-term ecological health and condition are threatened by both the fine-scale threat of non-native species introductions as well as broad-scale climate change. Climate change may facilitate invasion by non-native fishes, with the attendant warmer water temperatures, reduced ice cover and winter hypoxia, altered stream flow regimes, and shifts in habitat structure (Rahel and Olden 2008). In addition, populations of warm water non-native fish species such as golden shiner and smallmouth bass are already present downstream of Wolf Lake in nearby waters (less than 3 km away) that include Catlin Lake and Deer Pond (Limburg 2002-2015, unpublished data; Schwender
1989).
Though the potential for invasion of Wolf Lake by non-native fish species has received little attention, invasive fish may be approaching from these neighboring lakes fewer than three kilometers away via the main Wolf Lake outlet stream. If invasion of
Wolf Lake were to occur, a variety of shifts in native fish populations would be expected.
For example, Weidel et al. (2007) showed that removal of non-native smallmouth bass from an Adirondack lake resulted in large increases in abundance of six native fish species. If non-natives colonized Wolf Lake, then the opposite would be expected: declines in abundance of heritage fish species.
In addition to the lack of basic data on fish species distribution and community composition along the Wolf Lake outlet stream, information is also lacking regarding the
movements of fishes along this tributary. Broadly speaking, a multitude of ecological factors prompt fish to move along streams, and the primary drivers of fish movement vary considerably among different species and individuals. Some example factors that
VI-8 seem to drive fish movement include stream flow, day length, water temperature, body
size, habitat complexity, season, and time of day (Albanese et al. 2004; Schmetterling
and Adams 2004). For example, the movement distance and direction of some fish species can vary seasonally in relation to spawning and overall stream ecosystem metabolism (Hall 1972) as well as in response to higher flow events (Gowan and Fausch
1996).
Moreover, some fish in streams may not disperse outside of a certain stream reach, whereas others may move great distances along the stream to far-off reaches
(Rodríguez 2002). Though one study cannot address all of these potential intricacies of
fish movement dynamics, a need for general information regarding which fish species
may be moving in the Wolf Lake outlet stream and how mobile they may be in the
summer months was identified. Fish movement is of particular interest in this case because of the possibility for non-native dispersal and invasion via the Wolf Lake outlet stream.
As proposed by Stager and Sanger (2003), one way to avoid potentially disruptive ecological effects from non-native colonization would be to install a passive fish barrier
downstream of the Wolf Lake outlet. A physical barrier of this type would have the
potential to inhibit all fish movement up or down the outlet stream. After the initial
construction and installation investment, barrier maintenance cost would be relatively
low and the native Wolf Lake fish community would be well protected from non-native invasion. However, a fish barrier would prevent all fish species (native and non-native) from moving upstream to the lake via the outlet stream. Although fish barriers would obviously prevent non-native invasion, they could also result in unwanted isolation or
VI-9 demographic shifts in existing lake fish populations if certain individuals, age classes, or species were no longer able to move into the lake. For example, if reproduction for a particular native fish species typically occurred downstream of the barrier, young fish would not be able to migrate back to the lake if a barrier were installed. Thus, this study
also considered the potentially detrimental effects of a barrier dam on native fish
population connectivity and whether or not the barrier could be constructed far enough
downstream of the outlet that native fishes could continue to use the outlet stream for
reproduction, winter refuge, and foraging.
Overall, this research project addressed urgent knowledge gaps related to fish
community composition, invasion potential, movement patterns, and perceived need for
fish movement inhibition in order to support ongoing maintenance of the ecological
integrity of Wolf Lake within the Hudson River headwaters. The study was guided by
three primary research objectives:
1. Describe the fish community present at several locations along the Wolf
Lake outlet stream with an emphasis on detecting non-native species.
2. Employ mark-recapture techniques to estimate the degree to which fishes
may be moving along the stream and among study sites.
3. Identify existing barriers to fish movement along the stream and propose
suitable locations for a barrier dam that would inhibit non-native fish
invasion of Wolf Lake.
VI-10 METHODS
Study Area and Sites
Field sampling for this study occurred from June-August 2015 at the Huntington
Wildlife Forest, a biological research station operated by the State University of New
York College of Environmental Science and Forestry (SUNY-ESF) in the town of
Newcomb in the central Adirondack Park, NY, USA (Figure 1). This 6,475 ha forest property contains about a dozen lakes and ponds that drain west and south into the Upper
Hudson River. The target lake for the study was Wolf Lake, a 14 m deep, 154-acre (0.62 km2) water body (Approximate coordinates: 44.02, -74.22). The lake drains via one outlet
stream that flows north-northwest to join Catlin Lake (Figure 2). In addition, a small inlet tributary enters the lake via beaver meadow wetlands also at the north end. Wolf Lake is at an elevation of 556 m and is surrounded by abundant natural wetlands and both managed and unmanaged 250-year-old mixed deciduous and conifer forest. The state- owned Adirondack High Peaks Wilderness borders the watershed to the northeast. Total monthly precipitation during the summer averages 103.7, 102.4, and 97.9 mm in June,
July, and August, respectively. In 2015, total monthly summer precipitation was 243.6,
84.1 and 69.3 mm respectively (NOAA 2015).
Five study sites were selected along the outlet stream in order to permit representative sampling of the fish community at both ends of the stream and also at locations between Wolf Lake and Catlin Lake (Figure 2; Table 2). From highest to lowest elevation, the sites included the Wolf Lake outlet (A), a stream reach ~400 m northwest and downstream of the outlet (B), a site just upstream of the Deer Pond Road crossing
(C), a site just upstream of the Shattuck Clearing Road crossing (D), and the Catlin Lake
VI-11 inlet (E, the most downstream possible site along the tributary). Study sites A and E at the ends of the Wolf Lake outlet stream were deep, lentic pool areas with fine sandy sediment, broad widths (>10 m), and minimal canopy cover.
In contrast, sites B-D were first order, high gradient reaches with a large proportion of boulder and cobble substrate, substantial canopy cover (>50%), narrower widths (<8 m), and alternating riffle/pool structure.
Figure 1: Map of Wolf Lake within the Hudson River Watershed. (Newcomb, NY, USA)
VI-12
Figure 2: Map of five study sites along the Wolf Lake outlet stream. (Newcomb, NY, USA)
Site Location Latitude Longitude Elevation (m) A Wolf Lake outlet 44.0287 -74.2200 556 B ~300 m downstream of outlet 44.0298 -74.2219 556 C Deer Pond Road crossing 44.0324 -74.2269 536 D Shattuck Clearing Road crossing 44.0301 -74.2538 508 E Catlin Lake inlet (end of stream) 44.0250 -74.2611 487
Table 2: Study site information for the Wolf Lake outlet stream. (Newcomb, NY, USA)
Field Sampling
Basic water quality measurements (electrical conductivity, temperature, pH) were taken at the stream sites in June and July 2015 using handheld meters (COM-100 Combo
Meter, HM Digital, Inc., Culver City, CA; EcoTestr pH meter, Oakton Instruments,
Vernon Hills, IL) prior to and concurrent with biological sampling. Biological sampling of stream fishes began 6 July 2015 using paired steel minnow traps (40 cm long, 22 cm central diameter, two 3-4 cm entrances, 0.5 cm square mesh) that were deployed without
VI-13 bait in the stream 1-3 m from the stream banks at each site, left overnight for an average of 22 hours, and checked regularly for captured fish. Site D site was sampled first from 6-
17 July for 23 initial trap-nights. Next, Site A was sampled from 20-25 July for 12 initial
trap-nights. Site B was then sampled from 28 July to 5 August for 8 initial trap-nights.
For initial minnow trap surveys at these three stream sites, captured fish were transferred to a cooler containing stream water, anesthetized using clove oil dissolved in 95% ethanol
(eugenol concentration 30-60 mg/L), measured (total length and mass), and marked using visible implant elastomer tagging (VIE, Northwest Marine Technology, Inc., Shaw
Island, WA). These relatively small, economical, and biologically benign tags have been tested in mark-recapture studies for a variety of fish species (Adams et al. 2000; Bolland
et al. 2009; Leblanc and Noakes 2012; Reeves and Buckmeier 2009).
Each individual received two 2-5 mm long subcutaneous VIE tags in adipose tissue behind the eyes or in proximal tissue near the base of the dorsal, caudal, and/or anal fins. For each species, every individual received a unique identifying tag based on the color (red or yellow) and body location (right eye, left eye, right anal fin, left anal fin, right caudal fin, left caudal fin, right dorsal fin, left dorsal fin) of the VIE tags (Figure 3).
VI-14
Figure 3: Fish marked with visible implant elastomer (VIE) tags.
VIE tags were prepared and injected following instructions provided by the
manufacturer (Northwest Marine Technology 2008; Northwest Marine Technology 2011) and Thomas Evans (PhD Candidate, SUNY-ESF). At two other stream sites, minnow traps were used to capture fish that were not marked, but identified and measured only.
This occurred at sites E (6-8 August, six trap-nights) and C (13-17 August, four trap-
nights). Finally, follow-up recapture minnow trap surveys were conducted at sites D
(eight trap-nights) and A (four trap-nights) in August and captured fishes were inspected
for VIE tags before release. Any recaptured fishes were anesthetized, measured, and
placed in recovery buckets before they were returned to the stream.
In addition to minnow trap surveys, a bi-directional weir “fence” made of
hardware cloth and wire mesh was constructed and deployed across the stream in July at
Site D and then Site B as a means of capturing fish and assessing direction of movement
along the stream. The design and deployment of this weir was based on studies conducted
by Gowan and Fausch (1996) and Hall (1972). Finally, snorkel surveys were also
conducted at Site A (Wolf Lake outlet) to visually identify other fish species and size
VI-15 classes that may not have been detected using minnow traps. Snorkel surveys are an
effective passive observation technique for fish (Chamberland et al. 2013; Hubert et al.
2012; White et al. 2012), and published recommendations were followed during single
pass zig-zagging swim surveys within the open pool at the beginning of the outlet stream
and also along the margin of Wolf Lake outlet. These surveys were timed and conducted
on three different sunny clear, days (9, 16, and 17 August 2015).
Stream Barrier Assessment
In addition to fish sampling at stream sites, the locations and types of existing natural and human-created barriers were recorded. Barriers included structures and physical features that likely inhibit fish movement along the stream, albeit ephemerally in most cases. Barriers were identified during walking surveys along the riparian zone of the
stream and by examining current Google satellite imagery for the study area. Barrier
scouting surveys were conducted in detail along two ~1 km sections of stream at either
end. These sections extended from the Wolf Lake outlet (site A) to downstream of site C
and from upstream of site D to site E at Catlin Lake (Figure 2). The remaining 1-2 km middle sections of the stream were not rigorously surveyed given the large beaver meadows in the riparian zones. These large, more open beaver-modified sections of the stream were considered to be a different class of barrier that may partially inhibit fish movement. Finally, an additional visual walking survey was conducted at the north end of Wolf Lake (east of Site A) where an inlet stream drains into a beaver meadow and then into the lake. Based on the July/August appearance and other characteristics of barriers,
VI-16 the degree to which the barrier would likely inhibit fish movement along the stream was
qualitatively estimated.
Data Analysis
Data organization, management, and descriptive analyses were conducted using
Microsoft Excel for Mac 2011 Version 14.5.5.
RESULTS
Water Quality
Streamwater pH approached neutral at study sites, with somewhat acidic levels at interior Sites C and D. In contrast, water pH at Site A and in Wolf Lake proper was more basic. Electrical conductivity (EC) was very low at all locations and approached that of distilled water. Water levels were very high in June (e.g. >1 m at Site D) due to twice- normal precipitation during that month, but dropped dramatically in July and August due to lower-than-normal precipitation (e.g. 0.25 m at Site D) . Water temperature fluctuated throughout the summer from a low of 15.7ºC at Site D in June to a high of 23.5ºC at Site
A in late July (Table 3).
VI-17
Date Site pH EC (μS/cm) T (ºC) 12-Jun-15 A 7.4 19.5 19.2 12-Jun-15 B 6.5 19.7 18.5
12-Jun-15 C 6.1 20.2 18.5
29-Jun-15 D 6.1 20.3 15.7
14-Jul-15 D 6.8 22.6 22.6 15-Jul-15 D 6.7 23.5 19.8 16-Jul-15 D 6.8 23.6 17.6 17-Jul-15 D 6.8 23.8 18.0 24-Jul-15 A 7.1 19.1 23.5 OVERALL MEAN 6.7 21.4 19.3 24-Jul-15 Wolf Lake 8.2 19.0 21.4 22-Jun-15 [Distilled Water] 7.9 4.5 21.7
Table 3: Water quality measurements for study locations along the Wolf Lake outlet stream and at Wolf Lake. (Newcomb, NY, USA; values are means from n=3 samples)
Fish Capture and Distribution
A total of 65 minnow trap-nights conducted in July and August 2015 at five stream study sites yielded 311 captured individuals representing 12 different species
(Table 4). The highest species richness was observed at Site E (Catlin Lake inlet), which was also the only study site where non-native species including smallmouth bass
(Micropterus dolomieu) were detected (Table 5). No fish were captured using the weir.
Species Trap-nights (#) Fish Fish per Site Richness Jul. (Mark) Aug. (Recap) Total Captured Trap-night A 6 12 4 16 125 7.8 B 5 8 0 8 59 7.4 C 3 0 4 4 36 9.0 D 6 23 8 31 66 2.1 E 7 0 6 6 25 4.2 All 12 TOTAL 43 22 65 311 MEAN 6.1
Table 4: Summary of fish capture data for the Wolf Lake outlet stream. (Newcomb, NY, USA)
VI-18
The most abundant fish species, creek chub (Semotilus atromaculatus), was present study sites, though more were present at interior stream Sites B-D. Other abundant species included: (1) redbreast sunfish (Lepomis auritus), the dominant species at the Wolf Lake outlet (Site A); (2) cutlips minnow (Exoglossum maxillingua), only found at Sites A and B; (3) common shiner (Luxilus cornutus), another species found mainly closer to Wolf Lake; and (4) blacknose dace (Rhinichthys atratulus), which was absent from the sites abutting Wolf Lake and Catlin Lake (Table 5). Creek chub represented more than one third of the fish community in the Wolf Lake outlet stream and the top five most abundant species made up more than 90% of the fish captured
(Table 6).
Common shiner had the largest mean size across all sites. Creek chubs captured at the Wolf Lake outlet (Site A) were notably larger than those present at downstream locations. This was also the case for common shiner (Figure 4). For all captured fish, most were 50-100 mm long and <10 g (Figure 5). Mean total length and mean mass were greatest at Site A. The smallest fish mean sizes included creek chub and redbreast sunfish at Site E (Catlin Lake). Similarly, Site E had the smallest mean total length and mass when all individuals were included (Tables 7 and 8).
VI-19 All Site Site Site Site Site Fish Species Sites A B C D E Creek chub (S. atromaculatus) 109 10 34 17 42 6 Redbreast sunfish (L. auritus) 75 57 8 5 2 3 Cutlips minnow (E. maxillingua) 41 36 5 0 0 0 Common shiner (L. cornutus) 34 19 10 0 5 0 Blacknose dace (R. atratulus) 29 0 2 14 13 0 Yellow perch (P. flavescens)*? 10 0 0 0 0 10 Northern redbelly dace (C. eos) 5 2 0 0 3 0 Largemouth bass (M. salmoides)* 2 0 0 0 0 2 Longnose dace (R. cataractae) 2 0 0 0 1 1 Smallmouth bass (M. dolomieu)* 2 0 0 0 0 2 Central mudminnow (U. limi) 1 0 0 0 0 1 White sucker (C. commersonii) 1 1 0 0 0 0 TOTAL 311 125 59 36 66 25 * = non-native fish species, *? = questionable non-native fish species (Stager et al. 2015)
Table 5: Raw abundance for fish species captured at five study sites along the Wolf Lake outlet stream.
Fish Species All Sites Site A Site B Site C Site D Site E Creek chub (S. atromaculatus) 35.0 8 57.6 47.2 63.6 24.0 Redbreast sunfish (L. auritus) 24.1 45.6 13.6 13.9 3.0 12.0 Cutlips minnow (E. maxillingua) 13.2 28.8 8.5 0 0 0 Common shiner (L. cornutus) 10.9 15.2 16.9 0 7.6 0 Blacknose dace (R. atratulus) 9.3 0 3.4 38.9 19.7 0 Yellow perch (P. flavescens)*? 3.2 0 0 0 0 40.0 Northern redbelly dace (C. eos) 1.6 1.6 0 0 4.5 0 Largemouth bass (M. salmoides)* 0.6 0 0 0 0 8.0 Longnose dace (R. cataractae) 0.6 0 0 0 1.5 4.0 Smallmouth bass (M. dolomieu)* 0.6 0 0 0 0 8.0 Central mudminnow (U. limi) 0.3 0 0 0 0 4.0 White sucker (C. commersonii) 0.3 0.8 0 0 0 0 * = non-native fish species, *? = questionable non-native fish species (Stager et al. 2015)
Table 6: Percent composition (%) for fish species captured at five study sites along the Wolf Lake outlet stream.
VI-20 Figure 4: Size distribution for common shiner (Luxilus cornutus) captured at sites along the Wolf Lake outlet stream (n=34 individuals).
Figure 5: Size distribution for all fish captured at sites along the Wolf Lake outlet stream (n=311 individuals).
VI-21 Fish Species All Sites Site A Site B Site C Site D Site E CC 75.7 ± 2.1, 109 119.0 ± 7.9, 10 74.6 ± 2.8, 34 65.2 ± 2.7, 17 73.5 ± 2.8, 42 54.8 ± 2.4, 6 RS 66.5 ± 1.7, 75 65.3 ± 2.0, 57 71.6 ± 4.9, 8 81.2 ± 2.2, 5 61.0 ± 5.0, 2 54.3 ± 3.9, 3 CM 79.1 ± 2.1, 41 78.4 ± 2.2, 36 83.8 ± 7.2, 5 ------CS 83.1 ± 2.9, 34 93.6 ± 2.0, 19 62.7 ± 3.0, 10 -- 84.0 ± 7.2, 5 -- BD 57.5 ± 0.9, 28 -- 63.0 ± 4.0, 2 56.4 ± 0.6, 14 57.8 ± 1.7, 12 -- All 71.9 ± 1.1, 310 77.9 ± 1.9, 125 72.6 ± 2.0, 59 64.0 ± 1.9, 36 70.4 ± 2.1, 65 56.1 ± 2.5, 25 CC = Creek chub (Semotilus atromaculatus) RS = Redbreast sunfish (Lepomis auritus) CM = Cutlips minnow (Exoglossum maxillingua) CS = Common shiner (Luxilus cornutus) BD = Blacknose dace (Rhinichthys atratulus) Table 7: Mean total length (mm) for five fish species at study sites along the Wolf Lake outlet stream. The highest mean for each species are in bold (Format: Mean ± one SE, Sample Size).
Fish Species All Sites Site A Site B Site C Site D Site E CC 4.9 ± 0.6, 109 17.2 ± 3.6, 10 3.9 ± 0.5, 34 2.4 ± 0.3, 17 4.3 ± 0.6, 42 1.6 ± 0.2, 6 RS 4.4 ± 0.4, 75 4.2 ± 0.4, 57 5.2 ± 1.2, 8 7.5 ± 0.7, 5 3.3 ± 0.5, 2 2.2 ± 0.5, 3 CM 5.1 ± 0.5, 41 4.9 ± 0.5, 36 6.3 ± 1.6, 5 ------CS 5.5 ± 0.6, 34 7.6 ± 0.7, 19 1.8 ± 0.2, 10 -- 5.1 ± 1.1, 5 -- BD 1.5 ± 0.1, 28 -- 1.7 ± 0.3, 2 1.3 ± 0.04, 14 1.7 ± 0.1, 12 -- All 4.4 ± 0.3, 310 5.9 ± 0.5, 125 3.8 ± 0.4, 59 2.7 ± 1.9, 36 3.7 ± 0.4, 65 1.8 ± 0.3, 25 CC = Creek chub (Semotilus atromaculatus) RS = Redbreast sunfish (Lepomis auritus) CM = Cutlips minnow (Exoglossum maxillingua) CS = Common shiner (Luxilus cornutus) Blacknose dace (Rhinichthys atratulus) Table 8: Mean mass (g) for five fish species at study sites along the Wolf Lake outlet stream. The highest mean for each species are in bold (Format: Mean ± one SE, Sample Size).
VI-22 Passive observation snorkel surveys at the Wolf Lake outlet (Site A) provided
further evidence for abundant creek chub, redbreast sunfish, common shiner, and also
northern redbelly dace (Chrosomus eos) at the stream-lake interface (Table 9). The
presence of northern redbelly dace was notable, as this species was not captured at Site A
during minnow trap surveys. In addition, three creek chub and six redbreast sunfish
observed during snorkel surveys were clearly larger than most of the fish captured using
minnow traps (i.e. >100 mm total length). In addition to the fish species observed at
study sites, a variety of “bycatch” species were found live in minnow traps including a
total of 14 crayfish (Order: Decapoda) at Sites A-D, seven eastern newts
(Notophthalamus viridescens) at Sites A and E, an American bullfrog tadpole (Lithobates
catesbeianus) at Site A, and one dragonfly larva (Order: Odonata) at Site E.
Location Date Time Min Fish Fish/Min Species Observed Pool 9-Aug-15 14:00 7.2 44 6.1 4 CC, 3 RS, 37 NRD
Entrance 9-Aug-15 14:21 6.1 16 2.6 5 CC, 3 RS, 8 NRD
Pool 16-Aug-15 10:54 7.3 11 1.5 5 CC, 3 RS, 3 NRD 5 RS, 25 CS, 5 Entrance 16-Aug-15 11:18 5.1 36 7.0 NRD, 1 CC 11 NRD, 5 RS, 1 Pool 17-Aug-15 11:59 7.7 19 2.5 CS, 2 CC 6 RS, 6 CC, 6 CS, Entrance 17-Aug-15 12:12 5.6 28 5.0 10 NRD CC = Creek chub (Semotilus atromaculatus) CS = Common shiner (Luxilus cornutus) NRD = Northern redbelly dace (Chrosomus eos) RS = Redbreast sunfish (Lepomis auritus)
Table 9: Summary of snorkel surveys at the Wolf Lake outlet (Site A). (Newcomb, NY, USA)
VI-23 Fish Recaptures
Of the 311 fish captured and measured in July during 43 minnow trap-nights, 201 individuals of seven species were marked using individually identifiable VIE tags. Most of the marked individuals were redbreast sunfish at Site A and creek chub at Sites B and
D (Table 10). A total of 13 individuals were recaptured during subsequent trap-nights at
Sites A, B, and D, though only two, a creek chub at Site D and a redbreast sunfish at Site
A, were captured again in August (Table 11). VIE tag loss was noted for these two recaptures, in both cases from the basal left side of the dorsal fin (size measurements and remaining tags confirmed individuals).
Fish Species Site A Site B Site D Total Blacknose dace (Rhinichthys atratulus) 0 2 12 14 Creek chub (Semotilus atromaculatus) 5 31 32 68 Common shiner (Luxilus cornutus) 16 7 5 28 Cutlips minnow (Exoglossum maxillingua) 28 5 0 33 Longnose dace (Rhinichthys cataractae) 0 0 1 1 Northern redbelly dace (Chrosomus eos) 1 0 3 4 Redbreast sunfish (Lepomis auritus) 44 8 1 53 TOTAL 94 53 54 201
Table 10: Summary of fish marked using visible implant elastomer (VIE) tags at three study sites along the Wolf Lake outlet stream. (Newcomb, NY, USA)
Stream Barriers
A total of seven potential barriers to fish movement were identified along the study stream (Table 12). These ranged from discrete, human constructed barriers
(culverts) to expansive, natural barriers (beaver meadow wetlands). All of these barriers appeared to have the ability to ephemerally inhibit fish movement along the stream.
VI-24 Based on field observations in August, the most likely to inhibit movement would be road culverts at Sites C and D, which were perched when stream flow was low. Similarly, fish movement between Wolf Lake and the outlet at Site A may be blocked if lake level becomes low enough for the sandy shallow entrance to the outlet pool to form a barrier.
The water depth in mid-August was <10 cm at this location and may have prevented some fish from entering or exiting the lake at the outlet.
Recap # Species Site Mark Date Recapture Date 1 CC D 7-Jul-15 8-Jul-15 2 CC D 7-Jul-15 8-Jul-15 3 CC D 8-Jul-15 9-Jul-15 4 CC D 7-Jul-15 14-Jul-15 5 BD D 14-Jul-15 15-Jul-15 6 CC D 14-Jul-15 15-Jul-15 7 RS A 23-Jul-15 25-Jul-15 8 CM A 24-Jul-15 25-Jul-15 9 CM A 24-Jul-15 25-Jul-15 10 CC B 29-Jul-15 30-Jul-15 11 CC B 29-Jul-15 30-Jul-15 12 CC D 15-Jul-15 6-Aug-15 13 RS A 24-Jul-15 17-Aug-15 BD = Blacknose dace (Rhinichthys atratulus) CC = Creek chub (Semotilus atromaculatus) CM = Cutlips minnow (Exoglossum maxillingua) RS = Redbreast sunfish (Lepomis auritus)
Table 11: List of recaptured individual fish for sites along the Wolf Lake outlet stream. (Newcomb, NY, USA)
VI-25 Sites # Nearby Lat. Lon. Obs. Date Type Description 1 A 44.0282 -74.2195 9-Aug-15 Shallow water At outlet entrance 2 B, C 44.0309 -74.2248 21-Jul-15 Subsurface flow Steep boulder reach 3 C 44.0324 -74.2269 21-Jul-15 Culvert 1 m double at road 4 C 44.0336 -74.2289 21-Jul-15 Beaver wetland <300 m DS of C 5 C 44.0345 -74.2362 (Imagery) Beaver wetland E end of #6 C, D 44.0329 -74.2437 (Imagery) Beaver wetland Large, >3 km long D 44.0319 -74.2521 2-Jul-15 Beaver wetland W end of #6 6 D 44.0301 -74.2538 2-Jul-15 Culvert 2 m double at road 7 E 44.0279 -74.2600 2-Jul-15 Beaver wetland 600+ m DS of D
Table 12: Potential barriers to fish movement along the Wolf Lake outlet stream. (Newcomb, NY, USA)
DISCUSSION
The first objective of this study was to describe the fish community along the
Wolf Lake outlet stream and note the presence of any non-native species. Species lists
were produced for five locations via minnow trapping and found only native species in
the stream; non-native species are unlikely to have traveled upstream toward Wolf Lake.
The presence of smallmouth bass (Micropterus dolomieu) and largemouth bass
(Micropterus salmoides) at the most downstream end of the stream was also confirmed;
therefore, the threat of future invasion should not be dismissed.
The species observed at upstream sites have all been recorded regularly in
previous lake and stream fish surveys at Huntington Wildlife Forest (Limburg 2002-2015 unpublished data; Schwender 1989). At the Wolf Lake outlet (Site A), it was somewhat surprising that only one white sucker (Catostomus commersonii) and no brown bullhead
(Ameiurus nebulosus) were captured, as these species have been reported as abundant in
Wolf Lake (Limburg 2002-2015 unpublished data; Schwender 1989; Stager and Sanger
2003). No brook trout (Salvelinus fontinalis) were found at any of the study sites despite
VI-26 historical records of this species in and near Wolf Lake and capture of this species by
Stager and Sanger (2003). This may be because minnow trapping may not be an effective way to capture this species, or because of the timing of this study.
The species distribution data from this study also provide some evidence for how different species may be using stream habitat. For example, blacknose dace (Rhinichthys atratulus) and creek chub (Semotilus atromaculatus) were much more common at rocky, narrow interior stream sites with riffle/pool structure and greater canopy cover than at the open, deep, and sandy sites on the edges of Wolf Lake (Site A) and Catlin Lake (E). In contrast, cutlips minnow (Exoglossum maxillingua) and common shiner (Luxilus cornutus) were much more prevalent close to Wolf Lake, suggesting that these species may not move very far downstream. However, some common shiner individuals were captured at Site D, indicating that individuals of this species may migrate upstream from
Catlin Lake or downstream from Wolf Lake for spawning. Indeed, it is likely that many of the common shiner captured in June and July were actively spawning based on their red-orange fins and consistency with reported spawning times for this species (Smith
1985). The presence of larger fish at the Wolf Lake outlet may indicate that mature individuals are more common in the lake itself and that the stream reaches near the lake outlet may be used only for seasonal spawning or as refugia by smaller/younger fish.
Because very few fish marked with visible implant elastomer (VIE) were recaptured, the location of fish migration along the stream could not be documented.
Though VIE tagging was efficient, tag loss was observed in the individuals that were recaptured, suggesting that other marked fish may have also lost tags. In addition, only
VI-27 201 individuals were marked, which did not yield enough recaptures to facilitate open population modeling.
Although this study provides clues as to how native fish may be using the outlet stream, more conclusive work would be needed to better understand fish movement patterns in this study system. Future studies may benefit from marking more individuals using VIE or from employing another type of marking device such as passive integrated transponder (PIT) tags, which can yield high recapture probabilities (Zydlewski et al.
2006). Further work should also consider capturing fish at other times of the year. Spring sampling (May-June) in particular may allow for more capture of migrating fish based on known reproductive phenology of species present in this stream (Smith 1985).
This study relied heavily on minnow trapping as the primary means of assessing the fish community. Directional data on fish movement by implementing a weir fence at two study sites was attempted, but no fish were captured using this method despite concerted troubleshooting efforts. The ineffectiveness of the weir was partly due to the large substrate at the study sites (large cobbles and boulders) and the variability in stream flow that made it difficult to install the weir properly. Rather extreme water level fluctuations between early and late summer may also have contributed to lack of success with the weir.
Though fish were effectively captured using minnow traps, this method did not provide directional movement information and was inherently limited because only fish below a certain size class could be captured. Electrofishing represents one solution to this problem, though this method was deemed impractical for this study area given the challenges of transporting equipment to remote sites, the extremely low electrical
VI-28 conductivity of the water (K. Limburg 2015, pers. comm.; B. Daniels, 2015, pers. comm.), and the risk of injuring or killing fish (Snyder 2003) in a heritage ecosystem.
The third objective of this study was to identify existing barriers to fish movement that may partially inhibit non-native fish dispersal upstream to Wolf Lake. Given the presence of two road crossings with seasonally-perched culverts and many beaver meadows/impounded wetlands along the length of the stream, it is likely that fish attempting to move from Catlin Lake or Deer Pond to Wolf Lake would encounter many challenges, although in theory this type of dispersal could still be possible given the right hydrological circumstances. For example, precipitation in June 2015 was much higher than average and may have provided connectivity during high streamflow period prior to commencement of this study (NOAA 2015). The ability of culverts, wetlands, and other barriers to inhibit fish movement could be tested experimentally by capturing fish upstream or downstream of barriers, marking these individuals, and releasing them at other locations. Recapture surveys could then reveal if marked individuals were able to move across different barriers.
Though existing natural and human constructed stream barriers may provide partial buffers against non-native invasion of Wolf Lake, a more sound way of making sure non-natives do not enter via the outlet stream would be to install a permanent barrier as Stager and Sanger (2003) proposed. However, low-head barrier dams are not
necessarily completely effective, as some species may still be able to move past them
even if other species are inhibited (Porto et al. 1999). To further protect Wolf Lake from
non-native invasion, a more detailed study would need to be conducted to examine where
a barrier dam would be most effective at inhibiting fish passage.
VI-29 Based on the findings of this study, a candidate location for a barrier dam could be just downstream of the Site C road crossing before the start of the “beaver meadow zone” that extends west for >2 km to Site D. The data suggest that cutlips minnow and common shiner are not present that far downstream from Wolf Lake, so the impacts of the barrier on these species could potentially be minimized. In addition to providing easier access to the stream, a barrier dam at this location would become part of several
“layers” of movement inhibition that would include existing beaver meadows, active beaver dams, the new barrier dam, and the road culverts.
Even if a barrier dam were installed, it would also make sense to regularly monitor the fish community present in the stream, especially upstream of Site D before the beaver wetland zone where a smaller stream drains south from Deer Pond, a body of water that contains golden shiner (Notemigonus crysoleucas) and yellow perch (Perca flavescens) (Schwender 1989). Creative monitoring techniques including passive observation snorkel surveys (Chamberland et al. 2013; Hubert et al. 2012; Thurow 1994;
White et al. 2012) could be employed alongside minnow trapping at inaccessible stream sites.
Given the existing evidence for genetically distinct heritage fish in the region
(Morse and Daniels 2009; Lafontaine and Dodson 1997), it may also be useful to examine the degree of genetic similarity between fish captured in Wolf Lake, in the upper reaches of the outlet stream, and downstream closer to Catlin Lake in order to ascertain how isolated fish may be in this stream. If fish in and near Wolf Lake were very different from individuals of the same species close to Catlin Lake, that evidence would suggest:
A) a low probability that fish are able to move from lake to lake the lake, and B) in-
VI-30 stream populations may be isolated from each other due to natural barriers. Therefore,
implications for future population viability and genetic structure are possible.
CONCLUSIONS
Overall, this study generated novel information on fish species distribution and community composition at several locations along the outlet stream linking an ecologically important heritage lake with other water bodies in the Upper Hudson River headwaters region of the central Adirondacks. An urgent knowledge gap highlighted by
Stager and Sanger (2003) was addressed: to clarify which fish species may be moving in and out of the heritage lake. Non-native fish species were not detected at stream sites close to Wolf Lake and therefore infer that invasion potential is currently low. However, regular fish monitoring surveys should continue so that can they be compared to the baseline data provided by this study. Finally, further studies should examine more rigorously the optimal location for a passive barrier dam and carefully consider the impacts such a barrier would have on native fish that continue to thrive in this Upper
Hudson heritage lake.
ACKNOWLEDGMENTS
We would like to thank the Hudson River Foundation for funding this research,
the staff of the Hudson River Foundation for their assistance with this report, and the staff and summer work-study students at the SUNY-ESF Huntington Wildlife Forest for
supporting field operations. Special thanks to Thomas Evans for instruction in fish
handling and VIE tagging procedures and to the following volunteers for additional
assistance with field sampling and equipment: Jesse Smith, Michaela Dunn, Kristen
Haynes, and Dr. David Beguin.
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VI-34