Many migratory birds living in areas under government protection face difficulty because of their migration patterns.
According to The Los Angeles Times, a new study found 91 percent of the world's migratory birds do not have enough space in their protected areas. Complicating the matter is some of the birds' migratory patterns take them to other countries on different continents.
Published in the journal Science, the new study detailed how vital providing better protection for migratory birds is for various reasons.
"Migratory species make major contributions to resource fluxes, biomass transfer, nutrient transport, predator-prey interactions, and food-web structure within and among ecosystems and play an important role in human culture," the researchers wrote in the study, according to The Times. "More than half of migratory birds across all major flyways have declined over the past 30 years."
The nine percent of the migratory birds that had adequate protection pales in comparison to the 45 percent of non-migratory birds that require no additional help from the government, BBC News reported.
"This is due mainly to unequal and ineffective protection across their migratory range and the places they stop to refuel along their routes," study lead author Claire Runge, of the University of Queensland, told BBC News. "A typical migratory bird relies on many different geographic locations throughout its annual cycle for food, rest and breeding.
"So even if we protect most of their breeding grounds, it's still not enough - threats somewhere else can affect the entire population."