Once a month we will be sharing a marine species reported via the Fair Isle Marine WhatsApp group. This group is a space for community members and visitors to the isle to share any interesting marine finds. These reports also contribute to marine species records for Fair Isle to help monitor changes in biodiversity.
This month we have this three-spined stickleback Gasterosteus aculeatus found at Muckle Uri Geo during the Big Rockpool Challenge session
Three-spined sticklebacks are commonly found in rockpools and are characterised (you guessed it) by the three spines on their backs, with a distinctive mottled green colouring and large eyes for their body size.
They may not look it, but three-spined sticklebacks are fierce predators! They hunt other small fish and invertebrates and are extremely territorial, protecting and guarding their nest of eggs before they hatch.
They are anadromous meaning they can live in seawater but breed in freshwater which makes them tolerant to changes in salinity which is why they can survive in small intertidal rockpools.
Photo credit: David Parnaby