A group of biologists from the University of Washington conducting research work on Rota recently spotted two rare migrant birds on the southern island.
Andria Kroner said in an email response to Saipan Tribune that she saw a Eurasian kestrel perched on the power lines across the baseball diamond in Sinapalo while driving through town on the morning of Oct. 11.
Kroner said her sighting may be the only second sighting on Rota, with the first one occurring in 1997. She said only a handful of sightings of this species has been recorded in Micronesia.
Another migrant bird, a Japanese sparrowhawk, was spotted on Nov. 2 by the group's field supervisors, Sarah Faegre and Phil Hannon.
“The sparrowhawk, like the kestrel, is a rare sighting and the bird is considered an occasional migrant to the CNMI,” said Kroner.
She explained that the period between September and March is considered migration season for birds, that time of the year when rare bird sightings in the Marianas are most likely to occur.
Kroner noted, though, that storms can push migrating birds off their normal migration track.
“It is likely that more observations of migrants will occur in the following months and it is even more likely following a storm,” said Kroner. “Many different types of birds are migrating during this season so it is impossible to predict exactly what you might see.”
According to Kroner, some bird species go through the Marianas as part of their normal migration route, with some even dwell on the islands for the entirety of the winter season in the northern hemisphere.
However, there are birds such as the Eurasian kestrel that generally take other routes but can get blown off course by large storms and that juveniles are more susceptible to getting off track, she said.