A Golden Christmas Beetle ( Anoplognathus aureus ) Photo : Alan Henderson
The beetles of summer
Summer in Australia signifies all sorts of occurrences in nature , and one which many people identify with is the appearance of Christmas beetles . These lovers of eucalypt leaves often emerge in early summer , as Christmas approaches . They are frequently seen together in large numbers , decorating gum trees in their own unique way .
Christmas beetles belong to the scarab family of beetles . We have over 30 species of Christmas beetles in Australia , with colour forms that include brown , green , blue and stunning gold . Many are found along the east coast , and in some regions have become more abundant where land clearing has provided extra grasslands for them to reproduce in .
The life cycle of these beetles is the same basic cycle as most beetles . Eggs are laid underground in grasslands adjacent to eucalypt trees or forests . The grubs ( larvae ) feed upon grass roots and their growth is dependent on soil temperature . Those in warmer climates may emerge a year later , whilst
A trio of Christmas Beetles ( Anoplognathus boisduvalii ) in a gum tree Photo : Alan Henderson
those in cooler regions may spend two years underground . The larvae are crescent-shaped with a pale , reddish-brown head and three pairs of legs , but can be quite difficult to distinguish from other beetle larvae .
After pupating , the adults time their emergence with warmer conditions and are also stimulated by rainfall . Different species will emerge at different times throughout the summer ; perhaps to avoid direct competition . Other factors can influence the exact timing of their emergence , such as seasonal variations in weather patterns . Most Christmas beetles emerge from November to February , but as we know many appear in late December .
Christmas beetles are good flyers and can cover distances of several kilometres . Many fly at dusk , and are often attracted to lights after dark and can end up buzzing around the front porch .
Adult beetles are voracious leaf-feeders and often congregate in groups to feed and find mates in a wide variety of gum trees . Such is their tendency to cluster that hundreds can be found in a single tree , while an identical adjacent tree remains empty . While on occasion these beetles can cause damage to trees , most will usually recover . As is repeatedly the case , the increasing severity of the impact of the beetles on some trees is the result of human ecological disturbance – the depletion of forests and the increase in grasslands as Christmas beetle breeding sites .
by Alan Henderson - Minibeast Wildlife www . minibeastwildlife . com . au
14 What ’ s On & Where To Go December 2017-January 2018