Rhinoceros Auklet
(Cerorhinca monocerata)


Picture of bird
© Andrew A Reding - License
For additional photos and vocalizations, visit Dendroica. (Link opens in a new window.)

Rhinoceros Auklets breed in colonies on offshore islands of the temperate North Pacific. Because they visit their colonies primarily at night and nest in deep burrows, it is difficult to monitor their abundance. Counts of occupied burrows suggest that the population's abundance has changed little relative to about 1970. However, disruptions in marine food webs and predator introductions have affected reproduction and survival. Rhinoceros Auklets are highly susceptible to mortality from entanglement in commercial gillnets. This species has been identified as a priority for conservation and/or stewardship in one or more Bird Conservation Region Strategies in Canada.


Listing of the main designations for the species
DesignationStatusDateSubspecies, population
IUCN (Global)Least Concern2012 
Wild Species (Canada)Secure2010 
Bird Conservation Region StrategyPriority Species2013 

Population status

Geographic areaStatusReliability
CanadaLittle ChangeMedium

Population estimate

Canada700,000 - 800,000 breeding birds

Distribution maps


Migration strategy, occurrence

Short-distance migrant

Responsibility for conservation of world population


Conservation and management

Predation from introduced raccoons has reduced counts at Helgesen and Saunders Islands in the Queen Charlotte Islands (Gaston and Dechesne 1996), but abundance in this region is generally increasing otherwise. Also, variability in reproductive success is related to disruptions in the marine food web (Gaston et al. 2009). Specifically, spring phytoplankton concentrations and subsequent recruitment of Pacific sandlance, Ammodytes hexapterus, an important component of the diet fed to nestlings, appear to be strong predictors of auklet breeding success, and vary among years in response to changing wind patterns (Borstad et al. 2011).


Bird conservation region strategies

Environment and Climate Change Canada and partners have developed Bird Conservation Region Strategies in each of Canada’s Bird Conservation Regions (BCRs). In these strategies, selected species are identified as priorities for one or more of the following reasons:

  • conservation concerns (i.e., species vulnerable due to population size, distribution, population trend, abundance, or threats)
  • stewardship responsibilities (i.e., species that typify the regional avifauna or have a large proportion of their range or population in the sub-region)
  • management concerns (i.e., species that require ongoing management because of their socio-economic importance as game species, or because of their impacts on other species or habitats)
  • other concerns (i.e., species deemed a priority by regional experts for other reasons than those listed above or because they are listed as species at risk or concern at the provincial level)

Select any of the sub-regions below to view the BCR strategy for additional details.

BCRs, marine biogeographic units, and sub-regions in which the species is listed as a priority
RegionSub-region and priority type
Northern Pacific RainforestNorthern Pacific Rainforest, sub-region and priority type: Pacific and Yukon Region


  • Borstad, G., W. Crawford, J.M. Hipfner, R. Thompson and K.D. Hyatt. 2011. Enviromental control of the breeding success of rhinoceros auklets at Triangle Island, British Columbia. Marine Ecology Progress Series 424:285-302.
  • Gaston, A.J. and S.B. Dechesne. 1996. Rhinoceros Auklet (Cerorhinca monocerata). The Birds of North America Online (A. Poole, Ed.). Cornell Lab of Ornithology, Ithaca, New York. Gaston, A.J. and S.B. Dechesne. 1996. Rhinoceros Auklet (Cerorhinca monocerata). The Birds of North America Online (A. Poole, Ed.). Cornell Lab of Ornithology, Ithaca, New York. (Link)
  • Gaston, A.J., D.F. Bertram, A.W. Boyne, J.W. Chardine, G. Davoren, A.W. Diamond, A. Hedd, W.A. Montevecchi, J.M. Hipfner, M.J.F. Lemon, M.L. Mallory, J.-F. Rail and G.J. Robertson. 2009. Changes in Canadian seabird populations and ecology since 1970 in relation to changes in oceanography and food webs. Environmental Reviews 17:267-286.