Widespread flooding occurred within the Ogmore catchment in the 1960s, particularly around Bridgend, and extensive damage resulted. Flood protection schemes have since been constructed in the areas of Bridgend, Aberkenfig, Treoes, Coychurch and Ewenny village. Those in Bridgend, the main town in the catchment, are notable in terms of their scale and visual impact. Regular maintenance work is undertaken at all sites where formal flood defences are in place. Works may include the removal of gravel shoals, dredging of the river channel and control of bankside vegetation in order to maintain the flow carrying capacity of the existing channel.

Such work is of paramount importance in the protection of property from flooding. In-river work can sometimes disturb fish populations, but a recent assessment on the Ogmore at Bridgend demonstrated that some significant maintenance works were unlikely to have had long term effects on fish populations, and in some cases provided an improved and more varied habitat through construction of small check weirs and pools and a two-stage channel. Other impacts in the catchment relate to loss of cover for fish and disturbance to spawning gravels. Impacts such as siltation of the bed tend to be relieved by winter floods, but can affect angling. Careful planning of such work following consultation with Agency conservation and fisheries staff and mitigation works, such as planting schemes, creation of additional in-river habitats reduces impacts to a minimum. Part of the control of bankside vegetation undertaken for flood defence purposes has involved a programme of spraying of Japanese Knotweed along sections of the river. Although this has been very successful in places, it does require repeated attention and a catchment-wide approach to deal properly wth the problem. The vast majority of works are necessary for public safety reasons, and should therefore be regarded as legitimate uses of the river.

• Predation. Whilst predation by birds was cited as a limiting factor in the consultation document, predation by other animals such as mink did not receive any coverage. This subject was raised during consultation with various stakeholders and local area staff. Predation is a natural part of salmon ecology, and in most cases both predator and prey have adapted to each other’s presence. Salmon and their predators should therefore coexist without there being a serious threat to fish stocks. Indeed predation, through removing weaker individuals, may even benefit stocks. However, this relationship is dynamic, and predators can exert considerable pressure on fish stocks at any one time.

Fish eating birds, particularly cormorants, are often held responsible by fishery owners and anglers for reducing fish stocks, in both coarse and salmonid fisheries. Recent research in England and Wales found that cormorant predation, on the two rivers studied, was mainly focused on coarse fish. The impacts of goosanders on salmonid fisheries were shown to be potentially greater, agreeing with findings from another recent study in Scotland. Both studies however, highlighted the inadequacy of fisheries data in accurately determining the extent of impact.

DEFRA and the National Assembly for Wales have established a licensing procedure for those seeking to control predation by avian predators. Licences to shoot birds are only granted where serious damage can be demonstrated at a specific fishery and where other deterrents have failed. The Agency does not support the killing of birds unless these factors have been addressed. The Agency will continue to provide information, on an impartial basis, to help determine the impact to the fisheries.

A leaflet ‘Cormorants – The Facts’ has been produced by a partnership of fisheries and conservation organisations to address concerns and to answer some of the questions most often asked about cormorants. The leaflet is not intended to present solutions to the cormorant problem; it provides facts about cormorant numbers, what they eat, damage caused to fisheries, and explains the legal and practical limitations to culling. This leaflet is available on the Agency’s website.

The Moran Committee Joint Bird Group has also recently published a booklet entitled ‘Protecting Your Fishery From Cormorants’. Further information can be obtained on the Salmon and Trout Association website.

Mink were also cited as a potential problem. Although mink do not appear to be a threat to fish stocks generally, any concentration of prey will attract predators, and mink can therefore cause problems on fish farms and in salmon spawning areas. However, mink are highly opportunistic predators, and will preferentially hunt for small mammals and waterfowl. Any authorised person can kill or take mink using any legal methods, and although DEFRA has long ended its programme of attempting eradication of mink, ADAS continue to offer advice on control. However the Agency wishes to discourage mink hunting where otters and other wildlife may be disturbed.
There is also a view that, in the countryside generally, mink have found a vacant niche, and that they are settling down to reach a balance with their prey. It is also interesting to note that mink are thought to be displaced by otters (EA, 1996).