Foraging Ecology
A young seal forages for prey in the coral reef. Photograph courtesy of PIFSC, NOAA Fisheries
Several studies have been initiated in the Northwestern Hawaiian
Islands and recently in the main Hawaiian Islands to characterize
habitat use (satellite telemetry, CRITTERCAM, time-depth
recorders), diet composition (scat/spew analysis, fatty acid
analysis), prey abundance (reef fish surveys, bottom trawls), and
monk seal carrying capacity of the NWHI (trophic ecosystem
models). These studies are greatly improving our understanding of
monk seal foraging behavior and habitat use.
Currently, NOAA Fisheries has joined with a Prescott Grant
recipient, Dr. Robert Braun, in conducting an
Epidemiological/Foraging Study. For this study, the Foraging
Ecology Team is deploying 12 satellite tags and time-depth
recorders on Hawaiian monk seals to track their movements around the main Hawaiian Islands.
Some questions scientists are attempting to answer are
- Where do monk seals forage?
- What are their most important foraging habitats?
- Are there differences in the habitats used by different age- and
sex-classes of monk seals?
- To what extent do monk seals forage away from the primary atolls
and islands?
-
What do monk seals eat?
-
Are there any differences in diet by the seal's age and sex
class?
- Are there seasonal and annual variation in their diet?
-
What is the relationship between foraging behavior, diet and
survival, and reproductive success?
- What is the distribution, abundance, and spatial and temporal
variability of likely fish competitors of monk seals?
- What is the response of prey and competitors to large-scale
environmental variability?
Read more about Hawaiian monk seal foraging ecology:
Abernathy, K.J.
1999. Foraging ecology of Hawaiian monk seals at French Frigate
Shoals, Hawaii. M.S. Thesis, University of Minnesota, 65 p.
Littnan, C., F.A. Parrish, J.D. Baker, and G.J. Marshall.
2004. [In Press] Evaluation of Possible Effects of Video Camera
Attachment on the Foraging Behavior of Immature Hawaiian Monk
Seals. Marine Mammal Science.
Goodman-Lowe, G.D. 1998
The diet of the Hawaiian monk seal,
Monachus schaundslandi, from the Northwestern
Hawaiian Islands during 1991-1994. Mar. Bio1.132:535-546.
Goodman-Lowe, G.D., S. Atkinson and J.R. Carpenter. 2001.
Gross anatomy of the gastrointestinal
tract of the Hawaiian monk seal, Monachus schauinslandi.
Pac. Sci. 55:399-407.
Goodman-Lowe, G.D., S.Atkinson and J.R. Carpenter. 1997.
Initial defecation time and rate of passage of
digesta in adult Hawaiian monk seals, Monachus
schaundslandi. Can. J. Zool. 75:433-438.
Goodman-Lowe, G.D. J.R. Carpenter, and S.Atkinson. 1999.
Assimilation efficiency of prey in the Hawaiian monk seal,
Monachus schauinslandi. Can.J. Zool. 77:653-660.
Goodman-Lowe, G.D. J.R. Caprpenter, S.Atkinson and H.Ako. 1999.
Nutrient, fatty acid, amino acid and mineral analysis of
natural prey of the Hawaiian monk seal, Monachus schauinslandi.
Comp. Biochem. and Physiol. Part A. 123:137-146.
Parrish, F.A., M.P. Craig, T.J. Ragen, G.J. Marshall, B.M.
Buhleier.
2000. Identifying diurnal foraging habitat of endangered Hawaiian
monk seals using a seal-mounted video camera. Marine Mammal
Science, 16(2):392-412.
Parrish, F.A., K. Abernathy, G.J. Marshall, B.M. Buhleier.
2002. Hawaiian monk seals (Monachus schauinslandi) foraging in
deep-water coral beds. Marine Mammal Science, 18(1): 244-258.
Parrish, F. A., G. J. Marshall, M. Heihaus, S. Canja, B. Becker,
R. Braun, and G. A. Antonelis.
2004. [In Press] Comparison of Immature and Adult Male Hawaiian
Monk Seals Foraging Behavior and Prey Assessment at French Frigate
Shoals, Hawaii. Marine Mammal Science.