Snapper guts wanted!

University of Auckland MSc student Jessica Marinovich is looking for help from recreational fishers to obtain snapper gut contents. Jessica’s study is investigating the role that snapper play in controlling kina (or sea urchin) populations on rocky reefs. 

If you have ever been for a dive or snorkel inside the Goat Island Marine Reserve near Leigh you will have had large snapper swim up to you, and you may have also noticed the abundance of kelp in the area. It’s likely that the two things are connected, with kina as the link. Kina are sea weed eaters, and if their populations are not regulated by predators like snapper or crayfish, their numbers can increase to the point where nearly all of the sea weed on rocky reefs is grazed away. This results in bare rock habitats known as “kina barrens”, which are common along most of northeastern New Zealand’s rocky coastline. Kina barrens are less productive than kelp forests because seaweed is a plant, capturing the suns energy into coastal ecosystems, and also providing three-dimensional structure that many fish and animal species benefit from.

Over the next few months Jessica is hoping to collect hundreds of snapper gut samples from recreational fishers who have caught snapper from the shallow rocky reefs in the Leigh, Tawharanui and Kawau areas. She will use these gut samples to figure out what snapper are eating, and specifically how much kina they are eating. This will help to establish whether snapper (and also what sized snapper) are regulating rocky reef communities and associated productivity.

If you fish in these areas and are keen to help please get in touch with Jessica to arrange for a sampling kit so you can freeze snapper guts for her.

[email protected]