I don't know about you, but I rarely get depressed.
Sure, the continuous battle to protect wildlife, fight for human rights and pressure the government to do this or that can be tiring, frustrating and, arguably, depressing, but this is now a constant frustration and it can be 'tuned out'.
When I really start to feel depressed about stuff is when I've been away in our 'secret corner' of Poland, watching huge numbers of species in rich habitats for two whole weeks, while around us extensive forest contains wolves, lynx, wildcats, pine martens, bears, wild boar, black woodpeckers, nutcrackers, lesser spotted woodpeckers and more bats than you can shake a stick at.
Why would I feel depressed after such an amazing experience, after watching beavers every day in our back garden, after seeing eagles soaring overhead and hearing corncrakes calling incessantly from the many flower-rich hay meadows?
Why would I feel depressed when I've been watching red-backed shrikes, storks, purple emperor butterflies, flycatchers and the occasional Ural owl?
I may even have seen another wolf (I've seen two so far, one at just 5m in full sunshine), or at least heard them howling, so why would I feel depressed?
Why would I feel depressed when I've been among like-minded folk photographing birds, butterflies, crickets, sand lizards and perhaps an adder, smooth snake, grass snake or slow worm in the sunshine all day?
Why would I feel depressed when my trail cameras give me fantastic videos of a pack of wolves or a lynx?
No, during these amazing trips I feel great and we all have an amazing time surrounded by more wildlife than it's possible to see in the UK, ever.
I get a bit sad when we have to leave and we head to the airport and again when we finally take off on our journey home, but I don't feel depressed then either.
A feeling of depression hits me a couple of hours later, as we fly over the UK coast and I look out of the window and down to the landscape below.
Thoughts like: "What have we done?"; "No wonder we have no wildlife left!"; "How can people talk about 'conserving biodiversity', when we don't have any?" cross my mind and I remember what we've just left in our 'secret corner' of Poland and compare it with the barren and denuded landscape below me as we cross the UK.
I can't wait to go back again in May and June and introduce a new group of UK ecologists, conservationists and naturalists to a landscape where we can see lots of familiar species, but in much higher numbers than in the UK, plus many species that are now very rare or extinct in the UK, plus a few bonus species that have never been here.
I can't wait to have something to focus my camera on again; a reason to carry it for miles, knowing that there'll be lots to photograph, not least the looks of amazement on my guests' faces as they decide what to look at next.
I want to show those whose job it is to conserve, restore and recreate habitats that we have many misconceptions in the UK about which species prefer which habitats and the way the habitats 'should' fit together for maximum biodiversity.
Simply put, if you've never seen a landscape that's directly comparable to the UK but that's heaving with a multitude of species, literally buzzing with life, you should definitely come with us and not just open your eyes to the scale of what we've lost, but also to what we need to do to get it back.
Just don't look out of the window as we fly back to the UK!