Rocky headwater streams have a characteristic seasonal fluctuation in flow volume. In the spring, when the snow melts and rains are heavy, rocky headwater streams can become torrents. However, by mid- to late summer, the streams can become so slow that they are stagnant.
There are several thousand occurrences statewide. Many documented occurrences have good viability and are protected on public land or private conservation land. This community has statewide distribution, and includes several high quality examples. The current trend of this community is probably stable for occurrences on public land, or declining slightly elsewhere due to moderate threats related to development pressure or alteration to the natural hydrology.
The number and miles of rocky headwater streams in New York have probably remained stable in recent decades as a result of water quality regulations. Several examples have shown improvement in water quality in recent decades attributed to improved treatment of municipal and industrial waste (Bode et al. 1993).
The number and miles of rocky headwater streams in New York are probably comparable to historical numbers, but the water quality of several of these rivers likely declined significantly prior to the enforcement of water quality regulations (New York State Department of Environmental Conservation, Division of Water 2000).
Rocky headwater streams are threatened by development and its associated run-off (e.g., residential, agricultural, roads, bridges), recreational overuse (e.g., ATVs, intensive fish stocking and removal, adjacent camping), and habitat alteration in the adjacent landscape (e.g., logging, pollution run-off). In addition, alteration to the natural hydrology (e.g., impoundments, blocked culverts, stream channelization, water diversions, bank stabilization), and reduction in water quality (e.g., siltation, trash, turbidity, septic and nutrient run-off, pesticides, water temperature increases) are threats to rocky headwater streams. A few rocky headwater streams are threatened by invasive, non-native plants and animals.
Where practical, establish and maintain a riparian buffer to reduce storm-water, pollution, and nutrient run-off, while simultaneously capturing sediments before they reach the stream. Buffer width should take into account the erodibility of the surrounding soils, slope steepness, and current land use. If possible, minimize the number and size of impervious surfaces in the surrounding landscape. Avoid habitat alteration within the stream and surrounding landscape. For example, roads should not be routed through the riparian buffer area. If the stream must be crossed, then bridges and boardwalks are preferred over filling and culverts. Restore rocky headwater streams that have been unnaturally disturbed (e.g., remove obsolete impoundments and hardened shorelines in order to restore the natural hydrology). Prevent the spread of invasive exotic species through appropriate direct management, and by minimizing potential dispersal corridors.
When considering road construction and other development activities, minimize actions that will change what water carries and how water travels to this community, both on the surface and underground. Water traveling over-the-ground as run-off usually carries an abundance of silt, clay, and other particulates during (and often after) a construction project. While still suspended in the water, these particulates make it difficult for aquatic animals to find food; after settling to the bottom of the stream, these particulates bury small plants and animals and alter the natural functions of the community in many other ways. Thus, road construction and development activities near this community type should strive to minimize particulate-laden run-off into this community. Water traveling on the ground or seeping through the ground also carries dissolved minerals and chemicals. Road salt, for example, is becoming an increasing problem both to natural communities and as a contaminant in household wells. Fertilizers, detergents, and other chemicals that increase the nutrient levels in wetlands cause algae blooms and eventually an oxygen-depleted environment where few animals can live. Herbicides and pesticides often travel far from where they are applied and have lasting effects on the quality of the natural community. So, road construction and other development activities should strive to consider: 1. how water moves through the ground, 2. the types of dissolved substances these development activities may release, and 3. how to minimize the potential for these dissolved substances to reach this natural community.
Survey for occurrences statewide to advance documentation and classification of rocky headwater streams. A statewide review of rocky headwater streams is desirable. Continue searching for large stream systems in good condition (A- to AB-ranked).
Research composition of rocky headwater streams statewide in order to characterize variations. Collect sufficient quantitative data to support the recognition of several distinct rocky headwater streams based on composition and by ecoregion.
This community is widespread throughout upstate New York north of the North Atlantic Coast Ecoregion. It is concentrated in the mountainous areas of upstate New York. Rocky headwater stream communities are likely to be represented by different variants corresponding to major watersheds and/or ecoregions.
The broadly-defined community may be worldwide. Examples with the greatest biotic affinities to New York occurrences are suspected to span north to southern Canada, west to Minnesota, southwest to Indiana and Tennessee, and southeast to Georgia.
Rocky headwater streams are small- to moderate-sized perennial cold water streams with rocky substrate and a moderate to steep gradient. These streams usually consist of a network of first- to second-order stream segments, and they typically include alternating riffle and pool sections. Waterfalls, chutes, flumes, and cascades are typically present. Rocky headwater streams have high water clarity and are well oxygenated. They are typically surrounded by upland forests and are situated in a confined valley. Species assemblages characteristic of riffles, rocky substrate, and high water quality dominate the community. Cold water fish species, including eastern blacknose dace (Rhinichthys atratulus), creek chub (Semotilus atromaculatus), common shiner (Luxilus cornutus), slimy sculpin (Cottus cognatus) or mottled sculpin (C. bairdi), and brook trout (Salvelinus fontinalis) are characteristic. Rainbow trout (Salmo gairdneri) and brown trout (S. trutta) are commonly seen introduced species. Characteristic macroinvertebrates include stoneflies (Plecoptera including Chloroperlidae, Leuctridae, Perlidae), mayflies (Ephemeroptera including Heptageniidae, Isonychia spp.), caddisflies (Trichoptera, including Rhyacophila spp., Neophylax spp., Goera spp., Glossosoma spp., Psilotreta spp., and especially Hydropsychidae), midges (Chironomidae), crayfish (Cambaridae including Cambarus robustus, C. bartonii), water penny beetle (Psephenidae), riffle beetles (Elmidae), craneflies (Tipulidae including Hexatoma spp.) and blackflies (Simulidae). Freshwater sponges may be abundant, coating rocks in some examples. Characteristic pool macroinvertebrates may include true bugs (Gerridae, Vellidae, and Mesovellidae). Mollusks are typically lacking or are very sparse and of low diversity. Rocky headwater streams typically have moderate cover of bryophytes and algae, but few larger, rooted plants. The aquatic lichen Dermatocarpon fluviatile may be abundant (Edinger et al. 2002).
Rocky headwater streams have continuous flow and are found in the upper reaches of a stream system. They tend to have few, if any, meanders and a rocky streambed. They usually flow quickly with relatively cool and clear water. They tend to flow through or along upland communities such as forests and shoreline outcrops. Rocky headwater streams are generally depicted as a single line on 7.5 minute USGS topgraphic maps (becoming a confined or unconfined river when depicted as two lines downstream at 1:24,000 scale).
Known examples of this community have been found at elevations between 95 feet and 4,315 feet.
Rocky headwater streams are scenic year-round, but streams with waterfalls tend to have greater flow in spring and early summer. Mid- to late summer is a good time to look for the diverse array of aquatic macroinvertebrates living in the streambed.
This figure helps visualize the structure and "look" or "feel" of a typical Rocky Headwater Stream. Each bar represents the amount of "coverage" for all the species growing at that height. Because layers overlap (shrubs may grow under trees, for example), the shaded regions can add up to more than 100%.
Bode, R.W., M.A. Novak, and L.E. Abele. 1993. Twenty year trends in water quality of rivers and streams in New York State based on macroinvertebrate data 1972-1992. New York Department of Environmental Conservation, Division of Water, Albany, NY.
Cornett, S.C. 1996. The trout streams of Allegany State Park. Unpublished report. New York State-DEC Bureau of Fisheries Region 9 - Olean. 33 pp.
Daniels, Robert.A. 1998. Fishes of Allegany State Park. Unpublished report submitted to the New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY.
Edinger, G. J., D. J. Evans, S. Gebauer, T. G. Howard, D. M. Hunt, and A. M. Olivero (editors). 2014. Ecological Communities of New York State. Second Edition. A revised and expanded edition of Carol Reschke’s Ecological Communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation, Albany, NY. https://www.nynhp.org/ecological-communities/
Edinger, Gregory J., D.J. Evans, Shane Gebauer, Timothy G. Howard, David M. Hunt, and Adele M. Olivero (editors). 2002. Ecological Communities of New York State. Second Edition. A revised and expanded edition of Carol Reschke's Ecological Communities of New York State. (Draft for review). New York Natural Heritage Program, New York State Department of Environmental Conservation. Albany, NY. 136 pp.
Hunt, David M. 2001. High Allegheny Plateau stream community inventory project: western New York portion. New York Natural Heritage Program, New York State Department of Environmental Conservation. Albany, NY. 13 pp.
New York Department of Environmental Conservation, Division of Water. 2000. New York State water quality 2000. October 2000. New York Department of Environmental Conservation, Division of Water, Albany, NY.
New York Natural Heritage Program. 2022. New York Natural Heritage Program Databases. Albany, NY.
Reschke, Carol. 1990. Ecological communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY. 96 pp. plus xi.
Slack, Nancy G. and J.M. Glime. 1985. Niche relationships of mountain stream bryophytes. Bryologist 88:7-18.
Smith, C.L. 1985. The Inland Fishes of New York State. New York State Department of Environmental Conservation. Albany, NY. 522pp.
Information for this guide was last updated on: March 27, 2017
Please cite this page as:
New York Natural Heritage Program. 2022. Online Conservation Guide for Rocky headwater stream. Available from: https://guides.nynhp.org/rocky-headwater-stream/. Accessed May 21, 2022.