Conservation does not mean the same as preservation, despite the popular synonymy of these two words. Preservation implies that something remains the same, is static and held in the same unchanging state. One can preserve an old book, or fruit, or traditions for instance. But one cannot preserve biodiversity because species change in abundance and distribution, regardless of the activities of humans. That’s just how nature is. One could take a deep time view of such change and consider the ancient habitats and organisms that built much of Britain’s underlying geology, as I mentioned when I described some walking on the Dorset coast a while back. But even over shorter time scales that are comprehendible to humans, biodiversity changes, by the day, the month and the year.
That’s where egrets, and the pitiful punning title of this post, come in. At the end of last week Karin and I spent a long weekend on the Suffolk coast, in the village of Walberswick. It’s an old stomping ground for Karin but I don’t really know this area very well at all. We spent our time talking and reconnecting, eating local food, drinking the good local Adnams beer, walking along the beaches, through saltmarsh and reed beds, and collecting stones and sea glass (I really like sea glass and have amassed bottles of the stuff over the years that we keep on sunny windowsills – think of it as aesthetic waste management). And we looked at birds as we encountered them in these rich, diverse habitats. Final total for the weekend was a respectable 37 species, including a few I couldn’t identify, helped along by a trip to the RSPB’s Minsmere Reserve (with, it seemed, every other birder in Suffolk; we had to queue to get into some hides).
Two of the species we saw were egrets, a common name that covers several genera in the heron family Ardeiedae. As the Wikipedia entry for egrets notes: “The distinction between a heron and an egret is rather vague, and depends more on appearance than biology”, as good an argument for the importance of scientific species names as any I’ve encountered.
The first of the two species I spotted was the Little Egret (Egretta garzetta), an elegantly roaming bird that actively hunts along river margins and through marshland and flooded fields. I was able to get within 10 metres or so of a bird at Walberswick and could admire its poised movements on vivid yellow feet, contrasting with black legs to make it look like a woman wearing footless stockings, as Karin put it (she took the photograph that accompanies this entry). The second species of egret was the Great White Egret (Ardea alba), a much taller bird than the first, and an ambush hunter; like the related Grey Heron its strategy is to stand still and wait until prey comes to it.
The earliest record of a Little Egret in Britain was almost 200 years ago, in East Yorkshire in 1826. However it is not known to have bred in this country until a pair did so in Dorset in 1996. In other words, just 20 years ago this was an uncommon bird in Britain whose rare arrival would have generated a flurry of local twitching. Now it hardly gets a mention on birding sites, we are so familiar with it. Not so the Great White Egret which still raises some excitement when it appears. Although this species was also recorded as early as 1821 in Britain, Great White Egrets only began to breed in Britain in 2012 and there is considerable anticipation that it will follow the Little Egret in expanding its population in this country.
We could add other birds to this list of species which have naturally colonised Britain within living memory, such as the almost ubiquitous Collared Dove (Streptopelia decaocto) as well as insects such as the Tree Bumblebee Bombus hypnorum and the Ivy Bee Colletes hederae. Others will undoubtedly follow in the future, and perhaps the Cattle Egret will be the next member of the heron family to take up permanent residence on our shores.
Of course the flip side of new arrivals such as these is extinction, a topic that I will return to at some point as we’re currently putting the finishing touches to what I hope will be an exciting new paper on British bee and wasp extinctions. Understanding the ebbs and flows of biodiversity over time requires data to be collected and we are fortunate in Britain to have a number of active monitoring schemes that regularly survey different groups of organisms. This activity is vital if we are to be able to monitor our wildlife and to take action if we see declines, though the most recent results for the Status of Priority Species index makes grim reading: the overall abundance of threatened species in the UK declined by 68% between 1970 and 2010. It’s a complex message, though, and there are some success stories within those statistics. But the animals that have fared worst have been the insects, particularly moths and some of the bees, wasps and ants.
Against this background of monitoring and decline I was happy to accept an invitation last week to attend a Defra-sponsored meeting at the Natural History Museum in London to discuss the setting up of an insect pollinator monitoring scheme. A group of about 50 scientists and conservationists discussed what such a scheme might look like and how it could be implemented. I’ll report back in more detail about this in the future once some decisions have been made as to how to proceed.
Meetings such as this, as well as being important in their own right, provide an opportunity to catch up with old friends and colleagues and discuss their latest work, or latest child/house move/job move, as appropriate. So it was good to have a couple of beers after the meeting and chat with a few people including Dave Goulson, arguably one of the most significant scientists working in British pollinator conservation, and an outspoken critic of the current use of neonicotinoid pesticides. Dave founded the Bumblebee Conservation Trust and has produced a lot of the scientific literature on bumblebees as he describes with wit and passion in his recent book A Sting in the Tale. I’ve known Dave for over twenty years (we were PhD students together) so I was a little embarrassed to ask him to sign my copy of his book, but as a collector of signed editions I wasn’t going to let the opportunity slip. Dave mentioned that the book has been shortlisted for the Samuel Johnson Prize and I hope it wins: ok, I’m biased, and can read it in Dave’s own voice which adds enormously to the book. But it’s a great read for anyone interested in pollinators, or conservation, or just in the processes which turn a natural history obsessed kid into a professional scientist.
This will be my last blog entry from Britain for a month; on 31st October I fly out to Brazil to spend time with André Rodrigo Rech, running a short pollination biology course, speaking at the Brazilian Botanical Congress, and conducting field work. I’ll try to blog as I go along. In a happy coincidence the Great White Egret is depicted on the Brazilian five real banknote. I’ll look out for it.