Volunteers in the sky attempt to keep watch on migrant boats

Migrants on an overcrowded wooden boat in the Mediterranean Sea (Renata Brito/AP)

A humanitarian effort seeking to assist in the rescue of migrants fleeing Libya to Europe by boat and monitor human rights violations has taken to the skies above the Mediterranean Sea.

The volunteers on board the Seabird watch from above as flimsy boats attempt the perilous crossing – with nearly 23,000 people now having died or gone missing while attempting to reach Europe since 2014, according to the UN.