Graph

Black-crowned Night-Heron
(Nycticorax nycticorax)

Breeding Bird Survey (BBS) - Canadian analysis

Additional information on: Breeding Bird Survey (BBS) - Canadian analysis

Geographic area or population: Canada

Graph showing the trend of the species through out the observed years
 
Listing of the threshold values that appear on the graph
Population below lowest acceptable levelGoal
0.135 0.18
Listing of the individual data points that make up the graph
YearAnnual IndexLower limitUpper limit
19700.1850.0930.631
19710.1660.0860.503
19720.1860.0990.542
19730.1760.0920.501
19740.1870.1010.544
19750.1630.0880.464
19760.1860.0980.5
19770.1770.0950.474
19780.1780.0980.475
19790.1660.090.442
19800.1710.0960.429
19810.1620.0890.408
19820.1610.090.395
19830.1490.0840.365
19840.1410.080.339
19850.1440.0810.338
19860.1440.0830.36
19870.1490.0860.42
19880.1430.0850.341
19890.140.0820.317
19900.1380.0820.304
19910.1440.0860.308
19920.1530.0910.332
19930.1270.0760.268
19940.1330.080.27
19950.1310.0780.27
19960.1260.0760.276
19970.1180.0690.239
19980.1130.0650.232
19990.1270.0780.25
20000.1140.0680.231
20010.1190.0720.224
20020.110.0660.217
20030.1090.0660.218
20040.1160.070.233
20050.1410.0840.281
20060.1120.0680.218
20070.1130.0670.213
20080.1050.0610.209
20090.1060.0610.21
20100.1070.060.215
20110.1110.0650.213
20120.1060.0610.203
20130.1110.0640.221
20140.1150.0650.24
20150.1090.0620.218
20160.110.0630.227

Notes on numeric data: Ex represents 10 to the power of x; For example 1.2345E-2 is equivalent to 0.012345