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💧 Freshwater Least Concern 🌡️ Temperate

Northern brook lamprey

Ichthyomyzon fossor Reighard & Cummins, 1916
Max Length
17 cm
Max Weight
-
Lifespan
6 yrs
Trophic Level
4.1
Depth
-
Climate
Temperate
Resilience
Low
Vulnerability
50.00/100
Typical Length
13.4 cm
Depth Zone
demersal

📖 Overview

Freshwater. Generally associated with warmwater habitats and tolerant of variation in terms of discharge, water temperature, and substrate. Mainly inhabits warmwater, isolated segments of moderate-sized to large streams with summer flows 0.03-31 m3/s, summer water temperatures 14-25.6 ˚C. Adults inhabit clean, clear gravel riffles and runs of small rivers. Ammocoetes occur in quiet water over sand, silt and debris. Metamorphosis occurs in late August to September, in Michigan and extends to early October in Québec . Non-parasitic, the adults and possibly the larger ammocoetes in the resting stage do not feed . Adults live less than 6 months. In Michigan, the spawning period is from 13 May to 6 July, at water temperatures between 12.8-23.3 ˚C, with peak spawning activity in late May to mid-June. In Québec, spawning occurs in May, at water temperatures between 12.8-17.2 °C, peaking at temperatures between 13.3-15.6 °C. Nests are usually in the open and are poorly defined, but have also been found downstream of large stones 18-36 cm in diameter, or on a patch of gravel downstream of a submerged log. The nests are found in streams having 3.5-8 m width, 10-61 cm depth, and 0.1-0.6 m3/s flow. Up to 13 spawning lampreys have been found in a nest. There are reported occurrences in Michigan of communal spawning of Northern Brook Lamprey with Silver Lamprey (Pine River), and of Northern Brook Lamprey with Sea Lamprey (Devils River). Fecundity, 1,200 eggs/female. During spawning, adults preyed upon by Ambloplites rupestris. In the Laurentian Great Lakes Basin, it has been negatively affected by control measures directed towards Petromyzon marinus, except for the chemosterilization of males, which affects only the latter species. Vladykov (1949) reported that in the province of Québec, Canada, fishermen use ammocoetes as bait for sportfishes .

Scientific Name
Ichthyomyzon fossor
Authority
Reighard & Cummins, 1916
Habitat
Freshwater
Climate
Temperate
IUCN Status
LC
Max Length
17 cm
Lifespan
6 years
Trophic Level
4.1
Resilience
Low
Vulnerability
50.00/100
Migration
Potamodromous
Water Temp
14–26 °C
Salinity
0–0.5 ppt

🐟 Physical Description

Adults: 8.6-16.6 cm TL. Body proportions, as percentage of TL (based on 59 specimens measuring 9.8-15.8 cm TL): prebranchial length, 7.4-9.9; branchial length, 8.7-11.9; trunk length, 46.7-54.6; tail length, 27.7-33.7; eye length, 1.0-2.0; disc length, 3.6-6.4. The urogenital papilla length, as a percentage of branchial length, in 25 spawning males measuring 9.9-14.95 cm TL, 6.7-21.7. Trunk myomeres, 47-58. Dentition: supraoral lamina, 1-4 unicuspid teeth, usually 2; infraoral lamina, 6-11 teeth, usually unicuspid but one may be bicuspid; 4 endolateral teeth on each side; 0-1, strong mode of 0, bicuspid endolaterals in total, the other endolaterals unicuspid; 1-3 rows of anterials; first row of anterials, 3 unicuspid teeth; 1-5 rows of exolaterals on each side, usually 3-4; 2-3 rows of posterials; first row of posterials, 10-11 unicuspid teeth; crest of transverse lingual lamina strongly w-shaped and with either indistinct or about 20 small cusps, the median one not enlarged; longitudinal lingual laminae with 17 cusps each. Marginal membrane vestigial. A small gular pouch is present in both males and females. Velar tentacles, 1-2, smooth. Body coloration (preserved) in adults darker (grayish brown) on the dorsal and upper lateral aspects and lighter (pale gray or silvery white) on the lower lateral and ventral aspects, giving a distinctly bicolored appearance. Lateral line neuromasts unpigmented. Extent of caudal fin pigmentation, 25% to more than 75%. Caudal fin shape, rounded.: eel-like.

🌀 Behaviour

Behavioural data for Northern brook lamprey is currently being reviewed.

🦐 Diet

As larve (ammocoetes), the northern brook lamprey are filter feeders; feeding primarily on detritus, zooplankton, algae, diatoms, bacteria, pollen and a host of other microorganisms as they remain burrowed in fine substrate in calm waters. The juveniles and adults have non-functional intestines and do not feed; juveniles drift for 4–6 months and the adults spawn and die shortly after spawning.

🥚 Reproduction

Size at Maturity
13.5cm TL

🌍 Habitat & Distribution

Freshwater; demersal; potamodromous . Temperate; 14°C - 26°C ; 50°N - 37°N North America: St.

🌿 Ecology

Zone Preferences
💧 Freshwater ⬇️ Benthic
Migration
Potamodromous
Trophic Level
4.1±0.7

📐 Morphometrics

Length–Weight Relationship: W = 0.00107 × L3.03 (TL)
Max TL
17cm

🌡️ Water Parameters & Tolerance

Temperature Range
14–26°C
Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2012

📊 Population Risk & Fisheries

Population Resilience
Low
Minimum doubling time
Fishing Vulnerability
50.00/100
Moderate-High vulnerability
Trophic Level
4.1
Apex / Top predator
Climate Zone
Temperate
Described By
Reighard & Cummins, 1916

🌐 Names & Taxonomy

Language Common Names
🇬🇧English northern brook lamprey
🇸🇦Arabic جلكى نهرية شمالية
🌍CES mihule michiganská
🇫🇮Finnish pohjannahkiainen
🇫🇷French lamproie de ruisseau septentrionale · lamproie du nord
🇷🇺Russian Мичиганская минога

Scientific Synonyms

Scientific Name Author Year Status
Ammocoetes borealis Agassiz 1850 Heterotypic
Ammocoetes unicolor DeKay 1842 Synonym

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 3 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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