The construction of the High Speed 2 railway line from London to Birmingham is a huge engineering project. Amongst the many tasks there has been the provision of a ‘bat tunnel’. An artificial tunnel, built over a section of the high speed line, to prevent bats being killed by fast trains as they fly over that particular section of line. Years ago an electrified line on the third rail system had small tunnels provided underneath the lines to give badgers safe passage.
One of the most amazing examples of applying measures to protect wildlife from danger can be found on Christmas Island in the Indian Ocean. Following the first major rainfall at the beginning of summer, millions of Christmas Island Red Crabs carpet the island as they migrate to the coast. These palm sized land crabs live in burrows in the rainforest for most of the time, feeding on leaves, fruits, flowers and seedlings, occasionally scavenging on dead crabs and birds.
Their young must, however, develop in the sea, thus, once a year both the males and females swarm in their countless millions to the coast to breed. The males arrive first to make burrows beside the shore. Females arrive then to mate with them and stay with the eggs while they develop, before they crawl out and release the eggs into the sea. Here the young hatch out as free swimming larvae. Although they are small and vulnerable to larger marine life, their vast number ensures that many survive to become tiny baby crabs ready to come ashore to the rainforest. When they reach maturity at about four to five years old they are ready for the yearly migration to the coast.
