Reintroducing choughs to Jersey is one of several conservation projects carried out by Birds On The Edge. Not actual birds, but a partnership between Durrell Wildlife Conservation Trust, the National Trust Jersey, and the States of Jersey.
The choughs are ambassadors for Birds On The Edge. To ensure choughs thrive in Jersey we need the other Birds On The Edge projects to succeed such as the sheep grazing project managed by the National Trust Jersey.
Choughs need short, grazed, coastal grassland for feeding and in Jersey a lot has disappeared under a blanket of bracken. Birds On The Edge is working remove bracken along specific sections of north coast. There are many ways this can be achieved, but it isn't easy.
It also grows back!
Bracken have thick root-like stems, called rhizomes, which grow underground. Rhizomes can grow up to six feet long so cutting it above ground won't stop it from growing.
They don't necessarily eat the bracken, but they trample the ground exposing the rhizomes and destroying them.
They eat the surrounding grass keeping it short for the insects and ultimately the birds that eat the insects.
Here in Jersey we use sheep. Multi-horned Manx Loagthan sheep to be precise. These are a primitive breed of sheep specially adapted to surviving on cliff faces. It is pretty impressive how far down they can get. The sheep are allowed to roam free around Sorel, but are closely managed by shepherd Aaron and his dog Mist. Take a look at this video filmed on the north coast where the reintroduced choughs live.
Only ewes and juveniles are kept at Sorel. The rams are kept separate because they can be quite aggressive during the breeding season and it might not go down too well with tourists.
All the lambing occurs off site too because it involves very intensive management. The lambs are moved to Sorel with their mums when they are a few months old. Today there are over 200 sheep at Sorel.
There are other benefits to keeping sheep and choughs together. One bonus is that the choughs use wool to line their nests and protect their eggs from damage. In other chough-friendly countries like Mongolia, it won't be sheep's wool but yaks' hair!
Whilst the adults are busy collecting the wool for productive purposes the juveniles just like to play around.
Another bonus might not be obvious and it is a little bit gross. Its their poo! Certain insects feed and lay their eggs in sheep dung. The larvae which grow in the dung are perfect snacks for choughs. That is where that long slender bill comes in. They probe the dung to pick out the insects.
If you go walking in Cornwall or Wales look for cow pats with lots of small holes in and somewhere nearby will be a chough! Check out the ITV news video here for more information about how choughs returned to Cornwall.
Dung beetles are very important to the health of cattle herds and the land on which they graze. If we had no dung beetles, fields would be knee-deep in cattle dung.
It is estimated that dung beetles save UK cattle farmers an estimated £367 million each year.
Dung beetles play key roles in improving soils and controlling pests, the beetles and their grubs are food for wild birds and mammals, however, they are becoming scarcer and could even face extinction.
During a previous visit the team stumbled upon a gem hiding in a cow pat. A rare, tiny dung beetle known as Aphodius affinis so small it fits on the tip of your pinky finger.
Some of these dung beetle species rely on sheep poo (some have adapted to become dependent on dog poo too!). By keeping sheep at Sorel to graze the land it will create dung beetle friendly habitat. In turn this provides more food for the choughs. In their own way the choughs 'help' the beetles to remove dung by breaking it apart to search for the beetle larvae.
- Why is bracken bad for choughs and other insect eating birds?
- Can you list three ways sheep help choughs?
- Where else in the UK does grazing benefit chough populations?