Bats and birds increase crop yield in tropical agroforestry landscapes

"Ecology Letters": Bats and birds increase crop yield in tropical agroforestry landscapes. Abstract
 
"We found that bat and bird exclusion increased insect herbivore abundance, despite the concurrent release of mesopredators such as ants and spiders, and negatively affected fruit development, with final crop yield... Our results highlight the tremendous economic impact of common insectivorous birds and bats, which need to become an essential part of sustainable landscape management."


Insect-munching bats spare the chemicals. abc 240305

"Farmers can reduce the need to spray their crops with insecticide by encouraging insect-eating bats to roost in old hollow trees in their properties...There are about 90 species of bats in Australia, three quarters of which subsist solely on insects and spiders...The smallest species of bat in south-eastern Australia is the little forest bat (Vespadelus vulturnus), weighing in at just four grams. It gorges itself on mosquitos, while the southern free tailed bat (Mormopterus) feasts on the destructive Rutherglen, or seed bug ( Nysius vinitor)."

"Many farmers are unaware of the benefits of insect-eating bats... and often don't even know they have the tiny nocturnal mammals on their properties. Dr Lindy Lumsden "is encouraging them to preserve old dead trees on their properties so that bats can roost and breed in their hollow trunks...People often see a dead tree as just being good for firewood or a bit of an eyesore and cut them down...The main thing that farmers can do is maintain the remnant vegetation on their properties so the bats can breed themselves up....It takes around 80 to 100 years for tree hollows to develop, so farmers need to revegetate to ensure the trees that fall down and die, leaving bats homeless, are replaced in years to come."

Images:
Pisanello, Detail of Madonna of the Quail, 1420
Kaki Persimmon fruit, (Diospyros kaki)

Updates:
Native birds provide crop benefits, but Australian farmers treat them as a pest, abc 022014 

"Effects of land use on bird populations and pest control services on coffee farms” Railsback, S. F. and M. D. Johnson. Proceedings of the National Academy of Sciences USA, DOI: 10.1073/pnas.1320957111.  042014

Downturn in shade-grown coffee putting forests, wildlife, people at risk, mongabay, 07.2014

Shade coffee is for the birds 05022015

 Why shade-grown coffee is good for birds and farmers, The Conversation 26.02.2015