I'm surprised that I seem to be the first one struggling with this one as it's a stinker! Have loads I can't parse eg
16a Diving Bird and European deer spotted crossing mountain (5,5) - answer seems to be Emden Goose?
25a Cryptic description of corned beef that could kill you? (5) - toxin?
31a Scrutinising pounds invested in show by group (9) - exploring?
40a So English city mostly is covered by those on vacation (9) - therefore?
53a Bury and Manchester finally getting transport link (13) - interrealtion?
That's just the Acrosses!!