Mountain Brook Lamprey

Ichthyomyzon greeleyi Hubbs and Trautman, 1937

Ichthyomyzon greeleyi (Mountain Brook Lamprey)
NY Watershed Biosurvey (image provided by NYS DEC)

Petromyzontida (Lampreys)
Petromyzontidae (lampreys)
State Protection
Special Concern
Listed as Special Concern by New York State: at risk of becoming Threatened; not listed as Endangered or Threatened, but concern exists for its continued welfare in New York; NYS DEC may promulgate regulations as to the taking, importation, transportation, or possession as it deems necessary.
Federal Protection
Not Listed
State Conservation Status Rank
Imperiled in New York - Very vulnerable to disappearing from New York due to rarity or other factors; typically 6 to 20 populations or locations in New York, very few individuals, very restricted range, few remaining acres (or miles of stream), and/or steep declines.
Global Conservation Status Rank
Apparently Secure globally - Uncommon in the world but not rare; usually widespread, but may be rare in some parts of its range; possibly some cause for long-term concern due to declines or other factors.


Did you know?

Unlike some other lamprey species, the Mountain Brook Lamprey is nonparasitic and does not feed as an adult.

State Ranking Justification

New York is at the edge of the Mountain Brook Lamprey range where it only occurs in the Allegheny River Basin in Chautauqua and Cattaraugus Counties. It has only been found in small numbers, though its known range has increased, and population numbers appear stable (Li et al. 2014, Grasso 2023). It is considered uncommon through most of its range (Lee et al. 1980). However, accurate numbers can be difficult to ascertain due to the short time adults are available for capture and the difficulty in capturing and identifying larvae. This lamprey was found in less than 1% of fish survey samples (Carlson et al. 1999).

Short-term Trends

The range for this species appears to have increased in New York over the last 20 years. Population numbers seem to have remained stable, although abundance is difficult to determine (Li et al. 2014, Grasso 2023).

Long-term Trends

Over the long-term, this species appears to have declined. Some populations within their known range have been extirpated (NatureServe 2023). Carlson et al. (1999) found 3 historical records of Mountain Brook Lamprey in the Allegheny River Watershed in New York dating from 1937-1974, but only 1 record between 1975 and 1994.

Conservation and Management


Any activity which might lead to water contamination, siltation, warming of waterways, or the alteration of natural hydrology could directly and indirectly impact riparian habitats and Mountain Brook Lamprey populations. Such threats might include roadway and agricultural runoff, industrial pollution, dams, bridge construction and maintenance, logging activities, and development near riparian habitats (NYS DEC 2005). In addition, siltation decreases the amount of sunlight that reaches aquatic plants (EPA 2005) and lowers the quality of habitats needed for a variety of aquatic species (NYS DEC 2005). Point source pollution, such as effluents from municipal and industrial facilities, contribute to the degradation and pollution of aquatic habitats (EPA 2022, NYS DEC 2005, Mahar and Landry 2013, Strayer et al. 2004).
Altering natural waterflow can degrade habitat and restrict species movement. Dams directly restrict or impede species movement, alter the flow of water, change the water temperature, and contribute to sedimentation (NYS DEC 2005, Zaidel et al. 2021).
While modern day agricultural and silvicultural practices are an important aspect of the New York State economy, it is important to consider the effects on ecosystems and species. As these practices move closer to rivers, the natural riparian buffers are often removed. Riparian buffers maintain stream temperature and slow or prevent runoff of sediments from upland soil disturbances. Furthermore, they slow or reduce runoff from farm fields and pastures, such as contaminants from pesticides, fertilizers, manure, and sludge, into waterways (EPA 2005, NYS DEC 2005, Souza et al. 2020). Excessive fertilizer use can lead to algal blooms that can be deadly to aquatic life and overgrazing of livestock in fields could introduce pathogens, oxygen-demanding organics and solids, and invasive species to aquatic ecosystems (EPA 2005).
Approximately 10% of introduced, non-native species could have an impact on the health of ecosystems (McCormick et al. 2009). Invasive plants tend to outcompete native plants and can change natural processes (NYS DEC 2005). There is an increased risk of runoff and erosion when these plants are along streams and rivers. Aquatic invasive plants and animals can alter the water chemistry, change the nutrient regime, or decrease the dissolved oxygen levels. Introduced fish can alter trophic relationships resulting in a change in native fish populations and decreased water quality (McCormick et al. 2009).
Climate change is another threat that is likely to have lasting effects on riverine systems. Irregular weather patterns can cause extreme drought, flooding, and temperature fluctuations. Heat waves are expected to be more intense (Frankson et al. 2022). The Northeast Region of the United States is expected to experience an increase in precipitation, more frequent storms, and higher than normal temperatures (EPA 2016, EPA 2022). Precipitation is expected to increase 10% to 15% in southern New York and 15 to 20% in northern New York by 2050 (Frankson et al. 2022). Extreme flooding can cause widespread erosion and runoff with added risk of contamination if flooding occurs at remediation sites, industrial sites, or wastewater treatment facilities (EPA 2016, EPA 2022). Temperature increases can significantly alter ecosystems. As water temperatures rise, the amount of dissolved oxygen decreases and evaporation increases, potentially lowering lake and stream levels (EPA 2022). Any combination of these events could change species distributions (EPA 2022) and those that cannot adapt or migrate may be extirpated from some areas (NYS DEC 2005).

Conservation Strategies and Management Practices

Protect water quality and reduce contamination and hydrological alteration (such as agricultural or road runoff, shoreline development, and damming) (NYS DEC 2005). Protect stream quality by maintaining both a riparian buffer that includes herbaceous and/or woody vegetation along the shoreline, and a significant forested buffer. These buffers reduce sediment and contaminant runoff (EPA 2005, NYS DEC 2005, Souza et al. 2020), provide shade, regulate temperature, and provide organic matter to animals (Hughes and Vadas 2021). Riparian zones with herbaceous and woody vegetation have high “indicator scores” for macroinvertebrates and fishes (Hughes and Vadas 2021).
Remove barriers to maintain or restore natural flow to waterways. Where removal is not possible, research alternatives that allow flow above and below a barrier.
In general, avoid stream crossings. If crossings are unavoidable, use Best Management Practices (BMP) to minimize disturbance to streams. Time periods of disturbance when water flow is low or normal and install stream-crossing structures at a right angle to the stream (Watershed Agricultural Council Forestry Program 2018). Temporary methods to reduce runoff include water bars, gravel, geotextile fabric, rubber belt deflectors, open top culverts, straw bales, silt fencing, control blankets, and straw wattles (Watershed Agricultural Council Forestry Program 2018). Restore the disturbed area with native species as soon as possible. Areas that have been logged may also need ruts to be smoothed to reduce surface runoff (Watershed Agricultural Council Forestry Program 2018). Hughes and Vadas (2021) suggest that Best Management Practices may need to be applied to entire stream lengths and catchments to fully restore an aquatic ecosystem. If this is not possible, restore or manage a larger area around the directly disturbed area.
In general, tailor agricultural management plans to local conditions (e.g., soils, slope, land use). Often these plans aim to reduce pollution and increase farm productivity, but incentives could also be used to encourage sustainable farming practices. Proper management typically reduces runoff by 20-90% (EPA 2005). Consider using Integrated Pest Management (IPM) as an alternative to pesticide use. If pesticides and fertilizers are used, they should only be applied when needed, in the proper amount, and timed appropriately. In addition, rotate livestock to avoid overgrazing and to allow for vegetation regrowth. If needed, provide alternative water sources and shade to keep animals out of sensitive areas (EPA 2005).
Invasive species management can be time consuming and costly. Reduce the likelihood of non-native species being introduced into waterways. Boat-washing stations at boat launches can reduce transport of invasive plants and animals to new waterbodies. Educate anglers about the risk of releasing unused baitfish. If vulnerable species are present, consider a baitfish ban. Mechanical removal of some invasive plants may be needed in some rivers and streams. The use of pesticides to remove invasives can have a negative effect on ecosystems (McCormick et al. 2009) and should be a last resort to control invasive species.
Climate change is a global challenge. However, there are local actions that can help mitigate extreme weather events. Industrial and municipal infrastructure should be improved or replaced to be more resilient to flooding events (EPA 2016, NYS Comptroller 2023). Some suggested actions include installing or improving pumps to remove floodwater from facilities and installing protective structures, such as floodwalls. Ensure that existing bridges, dams, levees, seawalls, retaining walls, and wind barriers are prepared for extreme weather (NYS Comptroller 2023). Decrease runoff and erosion severity by installing large culverts, planting vegetation along riverbanks, and protecting and restoring wetlands (EPA 2016, NYS Comptroller 2023).

Research Needs

More research into the distribution, trends, and abundance of Mountain Brook Lamprey populations in New York is needed.



Mountain Brook Lamprey are known to inhabit clean-water creeks, eddies, and backwaters with low to high gradient almost exclusively and rarely move to larger rivers (Smith 1985, Page and Burr 2011).
Ammocoetes prefer shallow areas with fine sediment, slow water velocity, and higher temperatures, such as eddies and backwaters. These areas are usually upstream of obstructions such as culverts and dams, or at the edge of riparian zone (Li et al. 2014). Adults use gravel riffles and sandy runs of streams (Grasso 2023).

Associated Ecological Communities

  • Confined river* (guide)
    The aquatic community of relatively large, fast flowing sections of streams with a moderate to gentle gradient.

* probable association but not confirmed.


New York State Distribution

Mountain Brook Lamprey is found in Chautauqua and Cattaraugus counties in southwestern New York.

Global Distribution

This species ranges from northern Georgia, Alabama, and western North Carolina north to eastern Ohio, northwestern Pennsylvania, and southwestern New York.

Best Places to See

  • French Creek (Chautauqua County)

Identification Comments

General Description

The adult Mountain Brook Lamprey is bicolored, an olive tan above and a silvery tan below. The dorsal fin is a pale gray or yellow and notched. These colors are more sharply defined than in other lamprey species. The eyes are light gray and surrounded by gray blue. Adults also have approximately 57-60 trunk myomeres. The oral disc is as wide or wider than the head. The teeth are long, sharp, and moderately to well-developed and curved, and some of them are double pointed. The ammocoetes (larvae) are silvery tan with unpigmented ventral lateral line organs. The dorsal and lateral sensory organs are dark and inconspicuous (Smith 1985).

Characters Most Useful for Identification

The bicuspid teeth and single dorsal fin distinguish the Mountain Brook Lamprey from other lamprey species.

Best Life Stage for Proper Identification



Males build nests by moving pebbles to form a depression with a fine gravel and sand bottom where the eggs will be laid. Adults die after spawning. The larvae (ammocoetes) will float downstream after hatching before burrowing into a muddy area. They will filter feed until they transform into adults after approximately 5-6 years (Beamish and Austin 1985, Smith 1985).


This lamprey only feeds during the larval stage. Larvae are filter feeders.

Best Time to See

Mountain Brook Lamprey have been observed breeding in May in Pennsylvania (Lee et al. 1980). The larval stage lasts for several years. Larvae will transform into adults in the late fall or early spring (Smith 1985).

  • Active
  • Reproducing

The time of year you would expect to find Mountain Brook Lamprey active and reproducing in New York.

Similar Species

  • Ohio Lamprey (Ichthyomyzon bdellium)
    The Ohio Lamprey is parasitic and therefore has a functional gut unlike the Mountain Brook Lamprey which has a degenerate gut as an adult.
  • Northern Brook Lamprey (Ichthyomyzon fossor) (guide)
    Northern Brook Lamprey have fewer myomere and no bicuspid teeth.
  • Silver Lamprey (Ichthyomyzon unicuspis)
    Silver Lamprey have fewer myomere and no bicuspid teeth, and are generally larger on average than Mountain Brook Lamprey.

Mountain Brook Lamprey Images


Mountain Brook Lamprey
Ichthyomyzon greeleyi Hubbs and Trautman, 1937

  • Kingdom Animalia
    • Phylum Craniata
      • Class Petromyzontida (Lampreys)
        • Order Petromyzontiformes (Lampreys)
          • Family Petromyzontidae (lampreys)

Additional Resources


Beamish, F. W. H., and L. S. Austin. 1985. Growth of the mountain brook lamprey Ichthyomyzon greeleyi Hubbs and Trautman. Copeia 1985:881-890.

Carlson, D.M., R.A. Daniels and S.W. Eaton. 1999. Status of Fishes of the Allegheny River Watershed of New York State. Northeastern Naturalist 6(4):305-326.

Environmental Protection Agency (EPA). 2005. Protecting water quality from agricultural runoff.

Environmental Protection Agency (EPA). 2016. Adapting to climate change northeast.

Environmental Protection Agency (EPA). 2022. Region 2 climate adaptation implementation plan.

Frankson, R., Kunkel, K.E., Champion, S.M., Stewart, B.C., Sweet, W, DeGaetano, A.T., & Spaccio, J. (2022). New York State Climate Summary 2022. National Oceanic and Atmospheric Administration National Centers for Environmental Information.

Grasso, Kyle. 2023. New York State Department of Environmental Conservation species status assessment for Mountain Brook Lamprey (updated January 2023).

Hughes, Robert M., and Robert L. Vadas Jr. 2021. Agricultural Effects on Streams and Rivers: A Western USA Focus. Water 13, no. 14: 1901.

Lee, D. S., C. R. Gilbert, C. H. Hocutt, R. E. Jenkins, D. E. McAllister, and J. R. Stauffer, Jr. 1980. Atlas of North American freshwater fishes. North Carolina State Museum of Natural History, Raleigh, North Carolina. i-x + 854 pp.

Li, S., K-M. Werner and J.R. Stauffer Jr. 2014. An examination of Petromyzontidae in Pennsylvania: Current distribution and habitat preference of lampreys. Northeastern Naturalist 21(4):606-618.

Mahar, Amy and Jenny Landry. 2013. New York State Department of Environmental Conservation species status assessment for Lasmigona subviridis (Green Floater).

McCormick, Frank H., Glen C. Contreras, and Sherri L. Johnson. 2009. "Effects of nonindigenous invasive species on water quality and quantity." A dynamic invasive species research vision: opportunities and priorities 29 (2009): 111-120.

NatureServe. 2023. NatureServe Network Biodiversity Location Data accessed through NatureServe Explorer [web application]. NatureServe, Arlington, Virginia. Available

New York Natural Heritage Program. 2024. New York Natural Heritage Program Databases. Albany, NY.

New York State Comptroller. 2023. New York's local governments adapting to climate change: challenges, solutions, and costs.

New York State Department of Environmental Conservation. 2005. A strategy for conserving New York's fish and wildlife resources. Final submission draft.

New York State Department of Environmental Conservation. 2023. NYS DEC Rare fishes shapefile 1850 to 2022 (updated August 9. 2023).

Page, L. M., and B. M. Burr. 1991. A field guide to freshwater fishes: North America north of Mexico. Houghton Mifflin Company, Boston, Massachusetts. 432 pp.

Smith, C.L. 1985. The Inland Fishes of New York State. New York State Department of Environmental Conservation. Albany, NY. 522pp.

Souza, Francine N., Rodolfo Mariano, Tassio Moreia, and Sofia Campiolo. 2020. Influence of the landscape in different scales on the EPT community (Ephemeroptera, Plecoptera and Trichoptera) in the Atlantic Forest region. Environmental monitoring and assessment 129: 391-391.

Strayer, David L., J.A. Dowling, W.R. Haag, T.L. King, J.B. Layzer, T.J. Newton and S.J. Nichols. 2004. Changing perspectives on Pearly Mussels, North America's most Imperiled Animals. BioScience 54:429-439.

Watershed Agricultural Council Forestry Program. 2018. New York State forestry voluntary best management practices for water quality. Accessed on June 20, 2023.

Zaidel, Peter A., A. H. Roy, K. M. Houle, B. Lambert, B. H. Letcher, K. H. Nislow, C. Smith. 2021. Impacts of small dams on stream temperature. Ecological indicators 120:6-11.


About This Guide

This guide was authored by: Ashley R. Ballou

Information for this guide was last updated on: September 13, 2023

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Ichthyomyzon greeleyi. Available from: Accessed June 23, 2024.