But
smaller birds such as tits, which feed off larvae, struggle in the dry
conditions, the Danish
Ornithological Society (DOF) writes.
Waders,
birds that that wade in order to forage for food along shorelines and mudflats,
are also likely to see lean times as a result of the current weather, which can
dry out their habitats, the society writes on its website.
Furthermore,
low water levels in marshy areas highly populated by birds makes chicks more
vulnerable to attacks by predators.
“Most
small birds have already suffered their first challenges. That happened back at
the end of May, when the drought was not yet a serious problem. But now, after
no significant rain for more than two months, there could be a real problem
finding enough food for larva-eating birds like for great tits, blue tits and
other types of songbird, because the larvae dry out on the drought and the
heat,” DOF biologist Knud Flensted said via the organisation’s website.
This
year’s conditions are in contrast with the wet summer of 2017, when it was
swifts and swallows that struggled to find enough food for their young. This
year, dried-out fields provide more optimal conditions for the small birds to
find the insects they feed on.
Swift
chicks are capable of surviving for periods without eating if their parents
have to fly long distances to find food, but that has not been necessary this
year, DOF writes.
For
swallows, several broods with large numbers of chicks are likely if the stable
weather continues.
But on
the coasts, drought is a threat to several species of bird in marshy areas and
on islands.
“Gradual
drying out of the course of the summer in ponds and marshes is an advantage for
many waders if their young eat insects that live in shallow water. But this
year the marshes have dried out very early, so food reserves for lapwings,
redshanks and stints have shrunk and, in many places, disappeared completely in
breeding areas,” Flensted said.
“The
drought has also meant that foxes have had easier access to many birds’ eggs
and chicks. In particular where the low water has made it easy for predators to
reach spots that would usually be protected against uninvited guests,” the
biologist added.
Flensted
also noted that such a difference between two consecutive summers is a natural
variation.
Source: https://www.thelocal.dk/20180706/denmarks-drought-is-a-boon-for-some-insectivores-but-others-are-struggling