Nicole Nicolson, of Balclutha Primary School, asks :-

How many types of seahorses are there in New Zealand and what do they eat?

Chris Woods, a marine biologist with the National Institute of Water and the Atmosphere, and who has raised seahorses in aquariums, responded.

Seahorses are bony fishes whose closest relatives are the equally bizarre pipefishes and seadragons. Seahorses have a horse-like head (hence their name) with a tubular snout through which they suck their food. Their skin has an armour-like appearance and they have a monkey-like tail with which they use to cling to things.

There are around 35 identified species of seahorses.

In New Zealand, we have only one species of seahorse, the big-belly seahorse Hippocampus abdominalis, which also occurs in Australia. This species is found all around the coastline of New Zealand. They are usually found amongst seaweed, down to a depth of 40 metres, where they cling on to the seaweed using their tails. They are very shy fish and are difficult to spot because of their colouration, which they can change to blend in with the seaweeds they live in.

Seahorses mostly eat crustaceans such as shrimp, amphipods, isopods, and other small animals that live amongst seaweed and the surrounding water. In aquariums they will eat other prey such as brine shrimp and frozen mysid shrimps. As seahorses grow bigger the size of prey they feed on also increases. Seahorses feed by creating a strong suction force when they open their mouths, and suck their prey down their tube-like snout. Seahorses have no teeth, so their prey is either sucked down whole, or broken into smaller pieces with repeated snout-blows before being eaten.