On my recent trip to the subtropical gardens on Tresco, Isles of Scilly, one creature I was eager to see was this fella:
Now I had heard that stick-insects were living wild on the islands, but I hadn't twigged (groan!) that they would be so big. This is the Prickly Stick-insect from New Zealand, and those that I found were almost the length and thickness of a pencil. They were groovy!
What I also didn't know was that they can also be found in the St Mawes area of Cornwall, and around Torbay. Or that there were a further three species of stick-insect happily sitting about in bushes around Cornwall, Devon and Scilly.
Now I fully admit that I was really quite excited to find them. I have what I believe is in almost all of us - an instinctive fascination with other living things.
What is then really difficult is to put that natural curiosity to one side and consider how healthy it is to allow these creatures into our native ecosystems.
Now I'm not aware that any of the stick-insects are currently a problem, and they may never be. But consider this next example photographed in my garden, one of the commonest moths I see, and the first I found in the new RSPB South East office roof garden:
It is the Light-brown Apple Moth, from Australia, which has been accidentally introduced to North America, New Zealand, Hawaii and Europe, and whose caterpillar happily munches away at the leaves of all sorts of fruiting crops. Away from its native lands, it has few predators, and so has become a major pest in many places. The result? Many orchards use pesticides extensively to deal with it.
Or how about this, again photographed in my garden:
Yes, it's the Harlequin Ladybird from Asia, which is already the most widespread ladybird in America having arrived there in only 1988, and has almost spread from coast to coast in Britain since 2004. As you will know, there is deep concern about the effect it will have on our native ladybirds.
Now nature is often incredibly robust, in spite of everything we do. But faced with habitat fragmentation and degradation, with climate change, with chemical use, and with Man's capacity to spread disease and organisms around the globe as we're seeing with ash die-back, there are just those continual warning signs that as a society - and as gardeners - we need to be really really responsible if we are not to cause permanent and irreversible damage to our one and only planet.
So my stick-insect excitement was tempered with a nagging sense of concern. And I most certainly resisted any urge to smuggle one home in my rucksack!