Well I guess the seagull that Brightons are most familiar with is the European herring gull, here's a lovely quote on the wiki page:
To the seagulls credit, they are quite willing to approach and attack people, who are debatably the deadliest creatures on the planet. You have to be pretty hard...
Surprised this one has failed to get any nominations, probably because it's too obvious, but I shall nominate the Black Rhino. Both extremely aggressive yet a truly tough *******
Willing to second this, just look at this monster of an animal, it's also ****ING MAHOOSIVE
few creatures on this list can parallel the appearance of this prehistoric SOB, some of the largest are speculated to have weighed 100kg but there are allegations of one weighing 185kg, which is heavier...