Virgilio Vitug, director of the DENR’s Protected Areas and Wildlife Bureau, said all monitoring reports submitted by the regional offices did not show unusual deaths among migratory birds.
"This means that the Philippines remains bird flu-free," he said.
Vitug said an unusual number of deaths among the wild birds could be a probable sign that they are infected with H5N1 or other highly pathogenic subtypes of avian influenza.
Migratory birds are suspected carriers of the bird flu virus, which has infected millions of poultry in certain parts of the world.
According to latest reports, the bird flu virus has caused the deaths of 92 people since its outbreak in 2003.
Vitug said the Philippines is an important part of the Asian-Australasian migratory flyway, thus thousands of shorebirds pass through the country every year on their way to Australia.
The birds migrate to Australia to roost and escape the harsh winter in their countries of origin like China and Mongolia as well as in Siberia.
Vitug said migratory birds take temporary shelter in various wetlands, among them Olango Island in Cebu, Candaba Swamp in Pampanga, the Agusan and Liguasan marshes, and Naujan Lake, during their passage through the country.
The DENR strictly monitored the country’s more than 50 wetlands in the last quarter of 2005 in time for the arrival of the migratory birds to the Philippines.