Page 106 - Atlas Sea Birds Ver1

at the island (Cordes et al 1999, Crawford et al. 2007a, and had its base partially cemented, but by 1963 some
Kemper 2015a, Roux and Kemper 2015) that followed were using ground beyond the enclosure (Rand 1963). The
a collapse and northward contraction in the range of gannet colony also fragmented and the numbers breeding
Namibia’s sardine (Sardinops sagax), a main prey for both decreased from > 19,000 pairs in 1956 to just 126 pairs
these seabirds (Crawford 2007). Former large colonies in 2019, leading to concern that one of only six extant
of African Penguins at North Reef and Possession Island Cape Gannet colonies may soon be extinct (Sherley et al.
fragmented into smaller colonies, many of which became
extinct, and an increased proportion of penguins bred 2019). Numbers of Bank Cormorants breeding at the island
solitarily, some obtaining shade under bushes (Cordes decreased after the 1970s. About 30 pairs bred in 2020 and
et al. 1999). Gannets formerly bred in an area near the 2021. Possession Island is the only known, non-mainland
Possession Island jetty that was enclosed by a low wall breeding site of Damara Tern.

Estimated numbers (pairs) of different seabirds breeding at North Reef, 1956–2020
Year African Penguin Cape Cormorant Bank Cormorant Crowned Cormorant Kelp Gull

1956 850 29
1967 243 77
1978 151 1177 172 23
1979 630 162
1980 58 900 21 1
1985 0 533 34
1986 1 221 44 1
1987 2 114 207 4
1988 0 1268 5 4
1990 0
1991 0 24
1993 0 1
1995 0 6 1 4
1996 5
1998 2
1999 1
2000 3
2001 0 24
2004 0
2005 0
2006 0
2007 0 10
2008 0
2009 0 16
2010 14
2011 23
2016 11
2018 11
2019 0
2020 0

Cape Gannets breeding at Possession Island, January 1993 (photo RJM Crawford)

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