For the first time ever, Australia's only species of fishing bats have been recorded roosting and breeding in hotspots near some of Sydney's poshest harbour addresses.

Like black Tinkerbells, these endangered micro bats flit by in a blur at dusk, often playing before heading up local rivers to fish. The Large-footed Myotis (Myotis macropus) use their long clawed feet to scrape the water for fish and insects, which they find using echolocation, bouncing sounds off the water to detect minuscule movements by the fish.

In the gloaming last Sunday night, a colony of about 45 fishing bats started to stir in a massive underground cave beneath a jetty fronting luxury apartments in a secluded bay on Sydney's North Shore.