Calanus hyperboreus Kroyer, 1838
The largest, most abundant grazing copepod of the Arctic
Size
- Eggs 0.21 mm
- Females 5.9-7.4 mm prosome, 7.2-8.0 mm total length
- Males slightly smaller
Color & Characteristics
- Body almost completely transparent, red color may be prominant on antennae, mouth parts, and parts of the urosome (the tail)
- Lipid sac prominant, and up to 40% of body volume
- Urosome (tail) typical length (~ 20% of prosome)
- Antennae equal to or longer than total length
- Mouth parts and antennae typcial of filter-feeder
Habitat
- Endemic to arctic waters
- Most abundant in central basins, commonly advected onto deeper shelves
- Concentrated in surface waters during late spring to early fall, generally found below 500 m during winter
Feeding
- Suspension "filter"-feeder on phytoplankton and protists
- Large lipids deposits accumulated for over wintering stages
- Thought to be one of the arctic's key grazers
Life cycle
- Females spawn in winter using lipid reserves from previous year
- Clutch size dependent on size of female with maximums in excess of 300 eggs and typically 100-200 eggs, with over 1000 eggs per spawning season possible
- Nauplii complete development over spring/summer
- Late copepodites (CIII-CVI) overwinter at depth in 'diapause' (a form of hibernation), and may progress as little as one stage per season
- Generation length estimated at 3-4 years
- Life expectancy 3-5 years, with potential for females to spawn in sequential years
Page Author: Russ Hopcroft
Created: Sept 14, 2009
