For Dawn Chorus participants and bird song lovers everywhere, the ‘cuckoo!’ cry is one of the iconic sounds of spring. Sadly the common cuckoo bird is on the decline worldwide, partly due to the loss of suitable habitats and climate change. Specifically, the cuckoo, which migrates each year, is known for depositing its egg into the nest of a host which then incubates and feeds the cuckoo chicks that hatch. But while many other species are more flexible in their timing of arrival at their breeding grounds, the cuckoo’s return, each spring, is strongly predetermined. This means that the cuckoo’s highly specialized reproductive strategy (egg-dumping) becomes increasingly ineffective because their hosts may already have chicks or be done with their first clutch by the time the cuckoo lays its egg in their nest.
Bird song recording courtesy of Wikipedia Commons.
While the great tit is an extremely common bird (ranking second most recognised bird in Dawn Chorus), highly flexible in terms of both, nesting and food, they are likely to become endangered if the climate changes too quickly. The reason for this relates to food supplies. When spring arrives early, the trees leaf out earlier, causing the larvae that feed on these plants to emerge earlier. Since the great tit belongs to a group of species for which early chick survival depends on the abundance of these larvae, must correctly time its breeding to the ever-changing arrival of spring so as to successfully feed and raise its hatchlings. This fluctuating availability of peak food supplies could greatly put the great tit (and many other species) at risk.
Bird song recording courtesy of acclivity of freesound.org.
The house sparrow is one of the top three species recognized by Dawn Chorus participants for reasons obvious to those who love birds – these little fellows appear to be everywhere. This is partly because house sparrows prefer to live in urban and rural settings populated by humans. In Southern Germany, “Spatz” is even a common nickname for a loved one. At the same time, their numbers have drastically declined in some areas (as much as 60%), which is a major reason for concern. For example, in cities like Munich, the birds have almost disappeared for lack of nesting sites whereas in other places, their disappearance might be due to a variety of factors, including shortages of food, diseases such as avian malaria, and air pollution.
Bird song recording courtesy of Thomas Ryder Payne: Toronto based sound designer, composer, and musician.