COTW: Bat Deaths Linked to Increased Infant Mortality

A new study from a University of Chicago professor published in the journal Science says that when bats  die from widespread white-nose syndrome, farmers increase pesticide use by 31%.  This increase correlates with an increase in infant mortality in affected counties of 8%.  The study covered 245 counties from 2006 to 2017.  Damages from the fungal disease is estimated at $39.4 billion. [credit: Bat Conservation International; infected little brown bat]

White-nose syndrome, first detected in the mid 2000s, has now spread to 40 states and Canadian provinces killing 90% of populations among three species of bats.; These include the northern long-eared bat(Myotis septentrionalis) which is listed as endangered in the U.S.; the tricolored bat (Perimyotis subflavus) which is proposed to be federally protected as endangered in the U.S.; and the little brown bat (Myotis lucifugus) Bats are enormous insectivores, providing free insect eradication services to farmers. When that ecological service is lost due to disease, farmers resort to more pesticide use to keep food prices in-line. Multiple studies have found connections between infant health and pesticides that adversely affect environmental conditions.  A 2023 survey found pesticides in maternal serum, placenta and umbilical cord.  A bat conservation organization reported that 52% of bat species are at risk of extinction in the next 15 years.  The fungus inhibits bat's ability to  hibernate resulting in increased energy use and eventual starvation.  The fungus is thought to have been transported by humans from Europe. {05.26.2011}

Conservation efforts are underway, but the task is huge and complex.  Solutions will be several including vaccination, fungus eradication in known hibernation sites and increased forage efficiency by bats. The problem is nationwide, spreading from east to west beginning in 2006 and reaching the west coast by 2022 [map]: The study looked at other potential causes for the correlation such as unemployment and drug abuse, but found no other causes.  A reproductive epidemiologist at Harvard told the NYT that a growing body of research is showing the health effects of toxic chemical use in the environment although a precise cause and effect linkage has not yet been determined.  He is not afflicted with the new study, but the author Eyal Frank, has studied the effect of vulture die off in India that led to an increase of half a million deaths due to rotting livestock carcasses and an increase in feral dogs and water pollution.

His latest study has been called groundbreaking in its demonstration of the public health implications of ecosystem disruption.  Frank estimates base on his statistical study that 1,334 infants have died in affected counties.