|
Northern Brook Lamprey |
Scientific:
Ichthyomyzon fossor Reighard
and Cummins Description:
Adult 9-16 cm (3.6 – 6.4 in), Immature <12cm (< 5in) Egg size:
1.0 – 1.2 mm Adult:
A small, nonparasitic lamprey with small eyes and seven pairs of gill
openings. They have dark greyish brown backs and sides, and a pale grey
or silvery white belly. Spawning:
Northern brook lamprey spawn in
May or June when water temperatures are between 12oC and 16oC.
Spawning usually takes place in a shallow, pool-riffle, high-gradient
stretch of stream. Males
build a nest by moving small stones and sand with their mouth and body.
Lamprey spawn in groups and once eggs are laid and fertilized, the
adults die. Habitat:
Lives in freshwater
streams and rivers draining into Lakes Superior, Huron and Erie, Lake
Nipissing and in the Ottawa and St. Lawrence Rivers. Of particular
importance are rocky or gravel substrate with fast-moving water for
spawning and soft sandy areas with slower moving water for ammocoetes to
burrow. Life
History: They spend their entire life in freshwater streams and
rivers. Eggs hatch in the spring, a few weeks after spawning and the
ammocoetes dig a U-shaped burrow in the sand/silt substrate of the
stream bottom. The ammocoete stage lasts for 6 years, then transforms to
the adult. Lamprey live for 4 to 6 months as non-feeding adults, spawn
one time in May and then die shortly after. Ecological
Role: Filter feeders and play an important role in nutrient cycling
in streams. Adult and larval lampreys have also been used as biomonitors
of contaminants in fresh water systems because of their sedentary
nature. Similar
Species: Silver lamprey (Ichthyomyzon
unicuspis) Threats:
Sea lamprey control programs (lampricides) have negatively impacted
northern brook lamprey populations. Fluctuating water levels may be a
significant mortality factor for ammocoetes. The removal of riparian
vegetation may also contribute to declines in lamprey populations What
you can do: They are known to live in 4 tributaries of Lake
Nipissing. Protecting
watercourses and their riparian zones from habitat destruction and
alteration will benefit the northern brook lamprey populations. Report to the Natural Heritage Information Centre: http://nhic.mnr.gov.on.ca/nhic_.cfm.
Compiled
by: Rebecca Burns OMNR. |
||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
