This issue has attracted considerable attention recently, so I can appreciate your concern. As you know, it is lawful to kill a seal if it is deemed to pose a threat to fishing operations, in accordance with the Conservation of Seals Act 1970. I am sorry to have to tell you that I am not aware of any current plans to change this position.
Like you I would very much prefer to see non-lethal means of controlling seals being developed so that culling will no longer be thought necessary. I understand that such methods are already in use, and a representative of a Scottish aquaculture organisation recently stated that seals are only shot as a last resort. The fishing industry does argue, however, that culling is sometimes necessary to prevent damage to their operations.
On a more positive note I was pleased to see news in January that the seal colony on Blakeney Point in Norfolk has seen record growth in recent years, and is thriving. Apparently there was some concern that the population growth there might lead to calls for a cull, but the National Trust, which controls the property, has confirmed that there would be no need for this to be considered.