There's something fishy in London, and it's not the city's trademark fish and chips

Short-snouted seahorses have set up residence in the recovering River Thames, conservationists announced today

The fish—pictured above in the London Zoo aquarium—were found in recent surveys that assessed the health of the once heavily polluted river

The discovery of the animal in brackish tidal waters as far upriver as London was kept under wraps by the Zoological Society of London (ZSL) until the species had been granted protected status

Conservationists had feared that the bizarrely shaped fish might attract unwanted attention, such as from aquarium-trade collectors

The government declared the Thames biologically dead in the 1950s, and various groups have worked to rehabilitate it for the past two decades

These efforts have led to "a vast improvement" in the Thames' water quality, Shaw said

Seals, dolphins, salmon, and sea lampreys have also been seen swimming in the healthier river