Population status

Rhinoceros Auklet
(Cerorhinca monocerata)

The most reliable population trend data for Rhinoceros Auklet in Canada is from Environment and Climate Change Canada’s Seabird Colony Monitoring Program. Population trends are monitored at several of the largest breeding colonies by conducting burrow counts at fixed plots and estimating occupancy rates. These indices of population trend are available for four important colonies in the species’ Pacific range (S’Gang Gwaay, Lucy Island, Pine Island, and Triangle Island). At S’Gang Gwaay, there has been an increase since 1984, while at Pine Island, there has been a decline. The other two colonies show little overall change in population abundance. Dramatic declines in counts at two additional colonies are the result of predator introductions (Gaston and Dechesne 1996). Because these trends reflect this local conservation issue, they are less likely to reflect the population’s national status. Overall, the Canadian population has likely changed little relative to about 1970, but systematic monitoring information prior to 1984 is lacking. Consequently, the assessment of status is considered to only have moderate reliability. The Rhinoceros Auklet is at an acceptable level relative to its national population goal (see graph below).

 

Population goal and acceptable levels of variation

Species/groupGoalLower levelUpper level
Rhinoceros AukletMean abundance (first 5 years of survey)Goal minus 25% Not applicable

Seabird Colony Monitoring Program

Additional information on: Seabird Colony Monitoring Program

Table 1: Population trends by geographic area
Geographic areaTime PeriodAnnual Trend Table 1 - footnote 1 Limits
LowerUpper
Pacific coast Select to view graph of the geographic area: Pacific coast 1984-2017; Seabird Colony Monitoring Program1984-2017-0.2-0.60.3
 

British Columbia Coastal Waterbird Survey

Additional information on: British Columbia Coastal Waterbird Survey

Table 2: Population trends by geographic area
Geographic areaTime PeriodAnnual Trend Table 2 - footnote 1 Limits
LowerUpper
British Columbia coast1999-20162.4-13.418.5
 

References