Substitutes and Declines

It was feeling very spring-like today, I got very warm as I worked with the volunteers felling some grey alder beside the path to Lapwing Hide. These trees were planted as a “substitute” for native alder, which is not a hard tree to source, when the restoration planting was done after the gravel working ceased. Sadly truly native trees are not always specified in planting schemes, even when they are supposedly done for nature conservation and even when they are, substitutes are often allowed. Often even if the tree species is native they are not from a UK source, importing trees has brought us several diseases that have significantly impacted upon native woodland. These imports are also often adapted to a different climate so will flower or leaf earlier out of sync with native insects. Let’s have more native trees that are really native, ideally grown from the seed of trees as local to the planting site as possible.

wild daffodil

Wild daffodil just coming into flower, a good indicator of remaining ancient woodland at Blashford Lakes.

Having said all this planting trees is an often seriously over rated activity, if they establish well we end up with secondary woodland that will not be more than a pale shadow of an ancient woodland in even a thousand years. The best way to extend woodland cover is to allow existing ancient woods to grow outwards, letting them seed into neighbouring open ground, something that will happen naturally in most places if grazing or mowing are stopped. This way we will get locally adapted trees establishing where they will do best and other species can move out from the old wood into the new. It will also serve to buffer the older woodland and reduce the distance to the nearest neighbouring wood. I am prepared to make an exception for hedges though, so many of these have been lost that replanting is the only practical way to get them back, but the need for locally plant stock remains important.

There has been a good bit of coverage of the severe global decline in insect numbers in the media over the last few days and it is very alarming. A series of studies are now coming to very similar conclusions and these are that insects are in trouble globally with significant declines not just in developed western Europe but in tropical forests as well. Insects may be small but their abundance and diversity mean they are vital to the effective functioning of almost all terrestrial ecosystems. They are predators and prey, decomposers, pollinators and grazers, in fact they are almost everywhere and everywhere they are, they perform essential functions. I have run a moth trap for many years monitoring the species caught before releasing them and I can attest to a great drop in numbers over the years, I see as many species but none in great abundance as I used to.

pale brindled beauty

Pale brindled beauty, a typical late winter species, there were two in the trap last night.

Over the last few weeks things have been a bit hectic on the reserve with work going on all over the place, the new pond is being dug behind the Education Centre and preparations continuing for the installation of the new Tern hide next month. We are doing our best to keep the reserve up and running in the meantime, but there will be occasional interruptions to normal service, such as temporary closure of the main car park or limitations on the use of parts of the car parks.

Out on the reserve two bittern have been seen a number of times recently at Ivy North hide as have two great white egret. I am especially keen to try to record the last sighting of “Walter” our colour-ringed great white egret, he usually heads off back to France around this time of year so any definite sightings gratefully received. At the weekend an otter was seen at Ivy North hide and this morning I have very, very, brief views of one near Ivy South hide, so it is well worth keeping an eye out.

roost

A roosting great white egret with lots of cormorant, it might have been “Walter” but I could not see the legs to check for rings.

 

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30 Days Wild – Day 11 – Land of Giants

Another great night for moths, as anyone trying to sleep will have noticed, good moth nights tend to be too hot and windless for sleeping.  I caught 31 species in the garden and an impressive 46 at Blashford Lakes. I say impressive, but this is just for these days, catches of 80 or even 100 plus species were more common in days gone by and can still be achieved on the very best night at the best sites. There now seems to be no doubt that moths, along with perhaps all insects, have become less common. This seems to be a gross decline in numbers across the board, rather than a the extinction lost of species, although rarity does precede extinction.

It is very hard to say exactly why insects have declined but I think it is to do with human n=intervention in the environment, perhaps not a single cause but a combination of habitat degradation, nutrient enrichment, habitat fragmentation, chemical use etc. The sum of our many and various impacts on the world around us. I have run traps in more out of the way places where human impact is less obvious and have been impressed by the large number of individuals, even if not species that I have seen. Once in the far west of Ireland I saw several hundred garden tiger moths attracted to a single light trap, it was an extraordinary sight!

A 25 year long study of 63 nature reserve in Germany using a standardised collecting method concluded that flying insects of all types had declined by 75% during the study period, a truly shocking statistic an done that supports the gut feeling of most that look at insects here too. You can find out more on  Naturespot an excellent site that records wildlife across Leicestershire and Rutland.

puss moth

puss moth -one of my favourites from last night’s catch.

Moth traps do not only attract moths and last night at Blashford we caught a giant lacewing, these are really big, at least for lacewings. It is a species found in damp woodland that I have only ever found at a moth light, they must be hiding out there somewhere, but they are not the most obvious creatures when resting.

giant lacewing

giant lacewing

After a morning spent mowing bramble regrowth I was off the Fishlake to do a walk for Trust members. It was very hot in the sunshine and we enjoyed seeing a hobby and hearing a cuckoo.  The cuckoos will very soon be leaving us again, work by the British Trust for Ornithology (BTO) has shown that many of our cuckoos arrive here in mid April and leave by the end of June. How do they know? They have fitted a number of them with satellite tags and you can follow their progress at BTO Cuckoo tracking , it is a fascinating project and well worth a look.

Personally I enjoyed the sight of lots of male banded demoiselle jockeying for the best perches on the yellow water lily flowers along the barge canal.

What’s in My Meadow Today?

Back home I had a wander around the edge of the meadow and it struck me that I had not mentioned clovers, perhaps because they are in almost every patch of grassland, even maintained lawns. I have just the two most common species, the red and the white clover, but both are wonderful nectar sources for insects, especially bees. Clovers, like the rest of the pea family to which they belong have the ability to fix nitrogen from the atmosphere, which is why they were used in crop rotations before we had chemical fertilisers to increase the nitrogen content of our soils.

white clover

white clover

I think I will have a quiet night in today, last night I was tramping around a New Forest heath in search of nightjar for a survey being run by the Wildlife Trust. I enjoy a survey as much as the next person, but I confess that when I was crossing from one transect to the next and found that the “path” actually just lead into an uncrossable bog, resulting in the need for a nearly two mile detour, the appeal waned a little. I did find some churring nightjar though and heard a drumming snipe. These are two of the strangest natural sounds to be heard in this country and ones that, if you have not heard them on a dark June night, need to be added to your “Bucket lists”, a proper Wild Experience.