Nikkor 200-500 VR/TC 14 III @700mm, f8, ISO 640, shortly after sunrise; D750
crop (APS-H), Chinese muntjac (still shedding his coat), Lea Valley marshland/lakes;
archaic, non-herding deer, smaller than its Indian cousin. The males have small protruding tusks (among three other species currently living) they use along with their antlers during territorial disputes.
As the ecosystem function in Europe is broken in many ways, the defect is passed on back to people (abundant food/no predators/ excessive damage to remnants of woodlands) so as in other cases, the man has to monitor and fill in systematically for this crucial role to avoid significant collapses of the established system (they depend on) with the goal of a healthy population of deer that is slightly above an average of the natural balance.