Twitter feature locates rare birds in the borough

There is a Twitter service that allows users to subscribe to alerts showing where to spot rare bird species.
David Barrett runs a chain of popular bird alert accounts on Twitter. Using hashtags, his account sends automated tweeted tips about bird sightings.
Barrett has made accounts for four of the five boroughs and alerts almost 4,000 users across New York City.
In the Bronx, interested users can find the birds using the hashtag #BirdBX.
But not all birds make the cut. Barrett says only rare or interesting birds get reposted.