The human population is increasing rapidly, and demands urban landscape development. Contemporary urbanisation is expanding in such a way that previously natural areas are usurped for expansive growth resulting in protected and natural areas becoming islands embedded in an urban mosaic. This increases the interactions between humans and wildlife in the area. Human refuse, and plastics in particular, has become an increasing concern with wildlife, including seabirds.
The kelp gull. Refuse rummager. Beach bum. Awakening alarm. I am sure that many are familiar with the strident ‘kee-ah’ call of the kelp gull, one of 51 gull species worldwide. The kelp gull has a wide distribution throughout the southern hemisphere, and is increasing in various areas of the Cape provinces of South Africa. With many seabirds on the Red Data List, the kelp gull, along with a variety of other gull species, are increasing in numbers due to their ability to adapt to human activities. In Plettenberg Bay there are three main kelp gull colonies, and the one on Keurbooms Peninsula is the largest mainland colony in South Africa. On all three of these breeding colonies the evidence of humans is present. Plastic, especially, is found in nest bowls, and strewn throughout each colony, and not because people left litter there, but because the gulls brought these items to the colony. When the Robberg Road landfill was still open, kelp gulls were a familiar sight digging through the refuse. Outside houses on refuse collection day they have also learnt to tear open bags and dig through the rubbish. They will even take food from children on the playground, and from people on the beach. This penchant for junk food is understandably a concern, but rubbish is an easily accessible, dependable, year-round available food source – one can see the attraction. Kelp gulls are not the only species taking advantage of rubbish as a food source, here in Plett the sacred ibis has also become a regular sight tearing open refuse bags and leaving rubbish strewn across the verge. This highlights the need for improved waste management, where persistent wastes are separated from organic wastes that attract gulls and other species before disposal.
Written by: Minke Witteveen
For further reading:
- Crawford, R.J.M., Makhado, A.B., Waller, L.J. and Whittington, P.A. 2014. Winners and losers – responses to recent environmental change by South African seabirds that compete with purse-seine fisheries for food. Ostrich 85: 111-117.
- Whittington, P., Crawford, R.J.M., Martin, A.P., Randall, R.M., Brown, M., Ryan, P.G., Dyer, B.M., Harrison, K.B., Huisamen, J., Makhado, A.B., Upfold, L., Waller, L. and Witteveen, M. 2016. Recent trends of the Kelp Gull Larus dominicanus in South Africa. Waterbirds 39: 99-113.
- Witteveen, M., Brown, M. and Ryan, P.G. 2017. Anthropogenic debris in the nests of kelp gulls in South Africa. Marine Pollution Bulletin 114: 699-704.