Not everyone believes in global warming, after all, what happened to those glorious warm summers of our childhood? But it is here and real, with lots of evidence for the discerning. Bird observations offer a means of following global warming. Because many species have – locally – fairly specific altitudinal ranges, a new appearance of a bird above its traditional range might be significant. The principle is that birds, and indeed other animals and even plants, “follow” their preferred climate by moving up or down hill. Here at The Cavern bird observations have been made fairly systematically for about 45 years. The following species are “new”, and collectively suggest local warming. None are typical Berg birds, and some have never been seen at this altitude before.
Glossy Starling. Never present until about 1995. Now resident, with probably three pairs in the hotel surrounds. They are no longer confined to the garden, and are often seen in the acacias.
Black-collared Barbet. This has been resident since about 1997. About five pairs are present, loosely dependent upon the garden, but they also use scrub clumps in the veld.
Crested Barbet. First appearance here in 2002. Now established, probably two pairs. So far they seem confined to the garden and immediate surrounds.
Long-billed Crombec. Traditionally a thornveld bird, it first appeared here in 2005. The flat-topped Acacia sieberiana is the probable attraction. This tree is spreading up the valley, and this itself is a warming indicator.
Long-crested Eagle. Normally a mist-belt and coastal forest species, its first appearance here was in 2005.
Black Cuckoo-shrike. First appearance of three females was in 2006, and in the Fern Forest interior. This forest contains several warmth-loving trees usually found at lower altitude, and not found at Royal Natal just round the corner.
Spectacled Weaver. First appearance here in 2007. Now resident in the garden.