Hawaii Christmas Bird Count Data
More-recent trends in the occurrence of many bird species in Hawaii have
been inferred by data collected during Christmas Bird Counts through 2007
(see Introduction for more information).
Graphs have been prepared based on five Christmas Counts that have extended
consistently for at least 20 consecutive years, at Kapa'a (1971-2007)
and Lihue (1972-1992) on Kaua'i, at Waipi'o (1977-2007) and Honolulu (1944-2007)
on O'ahu, and at Volcano (1972-2007) on Hawai'i Island. Species were selected
based on observations of at least 70 individuals during at least 13 years
of the count, and graphs were prepared for species of interest and those
counts with trends or discernable cyclic patterns. Regressions were performed
on number of birds observed per party hour against year, and significant
trends (based on P < 0.05) are reported for species recorded
throughout the time frame of the count.
The following table indicates selected species and provides links to
graphs when created. In the table, "Increase" and "Decrease"
indicate species that either have significant trends throughout the count
period, or species with populations that either came into or became extirpated
from, respectively, the count circle during the period. "Cyclic"
indicates a species that shows apparent cycles, peaks, or periods of low
numbers within the count time frame but do not show significant overall
linear trends. Links to graphs are provided for species with increasing,
decreasing, and cyclic patterns. "No Trend" indicates stable
or fluctuating numbers but no significant linear trend or apparent cyclic
patterns; graphs were not created for most of these species.
Click on species name for pdf versions of species accounts.
Version 1 completed Dec 2009 and will not be updated for content
until Version 2 is posted (typos and bad links may be fixed). Plans are
to complete Version 2 sometime in 2011-2013, with further updated versions
to be completed every 2-4 years thereafter. Comments, errors, typos, bad
links, updated information, any other suggestions: Please contact Peter
Pyle at firstname.lastname@example.org.
Citation: Pyle, R.L., and P. Pyle. 2009. The Birds of the Hawaiian Islands:
Occurrence, History, Distribution, and Status. B.P. Bishop Museum, Honolulu,
HI, U.S.A. Version 1 (31 December 2009) http://hbs.bishopmuseum.org/birds/rlp-monograph