There will be no more migrants and most resident birds will relocate, so no need for binoculars anyway.
As others have suggested it's one for the crystal ball but if Brexit doesn't go smoothly (and the signs are not promising) then many are suggesting that the value of the £ against other currencies will drop. If so the price of imported optics (that's all of them!) will rise although, hopefully, not until retailers have sold their current stock.
How is Brexit working out so far ?
Jerry
That would be quite a funny question if it wasn't so tragic. The answer is very, very badly - from whichever angle you look at it. Never in living memory has a British government shown itself to be so utterly incompetent as our current one. They have had two years to plan for our country's future, but have wasted it with bickering and in-fighting to the extent that it looks like we will crash out of Europe on 29 March with hardly any proper plans in place. I think I had better stop there before I blow a gasket.
If the UK went to WTO rules and adopted a system of tariffs similar to Canada then binos might have a duty ranging from 0-6%. This after looking at several bewildering spreadsheets published on-line by WTO. Since the UK doesn't have a domestic bino-producing industry to protect then zero or a very low duty might be expected. Possibly.
If anybody with greater familiarity with HS Product Codes and tariffs disagrees I would welcome being corrected.
Lee