Sunday 29 October 2017

Clever Kestrels

I was really pleased yesterday to get a really good look at the kestrel which I often see hunting on the floodplains of the River Avon here in Ringwood.


I saw it again a few minutes later on my return journey where it kept hovering over the grass before diving down and catching a rodent. It then flew off with it's catch to a distant tree where I assume it ate it or possibly stored it for later.


It's likely that the catch was a vole as this is the most common prey that kestrels eat. They need to somewhere between four to eight voles every day(1) which is why they seem to always be hunting when you see them. As well as being able to hover on one spot they also have fantastic sight, being able to see and then catch a beetle from 50m away. Incredibly they are also ultraviolet sensitive which means they can follow the scent trails of rodents(2)! 

It's very nearly November but locally red admirals seem to still be doing very well. On one ivy bush I found three individuals and there are plenty still on the wing. 


In theory red admirals are butterflies which migrate to the UK from Europe but there is evidence that they are overwintering here in the South(3) and my personal experience would go along with that. Red admirals have one brood a year with the peak emergence being between mid-August and early-October(4). I am hypothesising that the emergence locally was towards the latter end of that period which would explain why there seem to be so many so late in the year. Of course the warmer temperatures mean they are thriving at the moment but this will only last for so long.

Walking along one of my favourite paths this week I was pleased to see large numbers of meadow pipits:

Meadow pipits are a relatively common bird in the UK thought numbers are declining. They can mostly be found in the uplands of the North of England and Scotland but they move south for the milder winter(5). Whilst they feed on invertebrates for most of the year, in winter they tend to eat seeds of grasses and heathers(6).

Up in some of the local trees are some sizeable mistletoe plants. 


Mistletoe is mainly found in the South of the UK and the West Midlands and most commonly, but not always, on apple trees(7). Although we regard them as parasitic they are technically only 'hemi-parasatic'- this means that they have their own green leaves for photosynthesis and only rely on the host tree for water and mineral nutrients(8). Generally mistletoe doesn't do significant harm to it's host, damaging a few branches but not killing the tree. 

Perhaps more common than mistletoe in our local trees at the moment are the grey squirrels


At this time of year grey squirrels are gathering food to store for winter. They don't hibernate and instead build thicker dreys where they can hide up in very cold weather and then go out and find their stored food(9).

You don't tend to imagine squirrels to have calls but they seem to be very local at the moment. They have a variety of calls but I think I've been hearing their territorial 'barks', presumably a noise used to tell other squirrels and competing animals not to come near their food stores. 

That's all for today and I shall see you in November.

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2: Viitala, J; Korplmaki, E,; Palokangas, P and Koivula, M. (1995) 'Attraction of kestrels to vole scent marks visible in ultraviolet light' Nature 373 (6513) pp. 425-427 (Online here).
6: Hoya, J. (ed) (2004) Handbook of the Birds of the World, vol. 9. Barcelona: Lynx Edicions. pp.763. 

Wednesday 25 October 2017

Awesome Autumn

It may well be Autumn but no-one seems to have told the temperature which is refusing to go as low as it should be at this time of year. That's good news for the butterflies though as they are able to keep flying. I've been seeing the occasional peacock butterfly and plenty of red admirals though on Sunday (22nd October) I was amazed to see a small copper.


Bear in mind that this little butterfly has survived the recent storms which though didn't affect us too badly here did give us strong winds and a lot of rain. There are usually two or three broods of small coppers a year but it's possible that this was a rare fourth brood, something which has been recorded in the South before. 

It's lovely to see butterflies so late in the year and I'm wondering if I might end up seeing one as late as November this year?

Whilst the number of invertebrates is significantly lower than it was a few weeks ago there are still plenty to be found if you look in the right places. Take this ivy bush which I passed today which was covered in buzzing insects. 



Ivy's late flowering is vital for insects. A 2014 study(1) discovered that an average of 89% of pollen pellets collected by honey bees during the Autumn come from ivy. The study also highlighted the importance of ivy flowers to other species such as bumble bees, common wasps, butterflies, hoverflies and other fly species. 

I walked part of the Stour Valley path near Throop on the edge of Bournemouth this week and saw a few birds of note. Flitting about on the concrete supports for one of the bridges was this grey wagtail

Grey wagtails spend most of the year around fast-flowing rivers where they feed on various aquatic invertebrates like flies, mayflies, and beetles and have even been recorded eating crustaceans and molluscs (2). In winter these birds move away from fast-flowing water and can be seen everywhere from gardens to city centres (3). It's interesting that this individual is still near fast-flowing water, perhaps indicating there is still enough food for it here at the moment.

Along the route I also spotted this magnificent grey heron


At this time of year grey herons have spread out away from their nesting colonies(4) and can be seen pretty much anywhere where there is water. Around harvest time they can often be seen in fields where they look for rodents to eat(5)- indeed I saw a heron catch and eat a rat in a field earlier in the year. 

I also saw a moorhen on the Stour too. 

Whilst UK moorhens stay here all year round they are joined in the winter by around 30,000 migrating birds from Europe(6).

One of the most common birds I've seen this week are pheasants. They are really tricky to get good photos of though as they run away from you so I've only ended up with pheasant heads stuck out over the top of a field and pheasants running away. 


Pheasants are not native to the UK but were introduced from Asia for hunting- indeed, it's thought that they are one of the world's most hunted birds(7). 

Pheasants are legally hunted between the 1st October and the 1st Febuary(8) each year. Beaters walk around in areas where pheasants, and other game birds like grouse, are likely to be which causes them to try and fly to safety where they are then shot down and collected by dogs. It disturbs me that killing things for sport is still perfectly legal in the UK in the 21st century. Not only is it legal, it's also big business. 

Landowners that have hunting interests are more likely to provide and manage good habitats than those without(9) and this is often used as a justification for hunting. The government should be working with landowners to ensure habitats are well managed instead of relying on people who want to kill things- that's not real conservation, it's just an accidental byproduct. There are also regular stories of birds of prey, including rare species like hen harriers, being killed in suspicious circumstances around grouse moors so they can't feed on chicks. 

I enjoy the bright colours of pheasants and the way they scuttle around is amusing but I always feel a certain melancholy when I see them knowing that their days are likely numbered thanks to the idiots who think killing living things counts as sport.

I've tried something new today and have put the sources to the information I've used here where I can. You may be interested in reading further on things I've talked about or they might just help to prove I'm not making things up!

                                                                                                                                                      

1: Garbuzov, M. and Ratnieks, F. (2014) 'Ivy: An underappreciated key resource to flower-visiting insects in autumn', Insect Conservation and Diversity, 7, (1), pp. 91-102.
2: Santamarina, J. (1989) 'The Grey Wagtail (Motacilla cinerea) diet in the Ulla river basin, Galicia. NW Spain'. Ardeola (in Spanish) 37 (1). pp 97-101. Link
7: Robertson, P. (1997) Pheasants. Voyageur Press. ISBN 0-89658-361-9.
8: Game Act 1831- online here.
9: Oldfield, T.E.E, Smith R.J., Harrop S.R. and Leader-Williams N. (2003) 'Field sports and conservation in the United Kingdom', Nature 423. pp 531-533

Sunday 15 October 2017

Lymington in October

Today I visited one of my favorite local nature reserves, Lymington-Keyhaven. With winter on the way it's starting to get busy with winter migrants.

Perhaps the easiest bird to see at the reserve, and indeed anywhere along the UK's coast, is the black-headed gull.


It's estimated that around two thirds of UK black-headed gulls in winter are actually migrants from mainland Europe. In winter these birds lose the chocolate-brown plumage which give them their name and just a brown smudge remains.

There were plenty of ducks on the reserve although most were females which look very similar and are difficult to identify from a distance on a murky day.


I suspect all or at least most of these ducks are wigeon- the bird in the top left is clearly a male wigeon. Wigeon do breed in the UK but only in Scotland and Northern England so these birds will be winter migrants from Iceland, Scandinavia or Russia.

Wigeons are dabbling ducks, like mallard, which means they feed by tipping headfirst into the water. The legs of dabbling ducks are more central than other types which means they can walk well on land and graze there.Diving ducks have to run across the water in order to gain momentum to take off whereas dabbling ducks are able to take flight straight from the water.


As you'd expect at this time of year there were plenty of waders around in the shallower water. I still find wader identification really tricky especially in winter when they tend to be similar light grey colours- it's highly possible some of my identifications are not right. 

There were many small waders which I think are probably dunlin- they are after all our most common small wader. 


Unlike other small waders, dunlin have slightly curved beaks which seems to be the main way to identify them. 

The largest waders of the day were the black-tailed godwits on the left of this photo.


It's interesting to see that these godwits still look fairly bright, not yet having faded to their full greyer winter plumage. I'm speculating that unlike other waders I saw, these are actually resident birds (I've certainly seen godwits at the reserve all year round) and therefore don't naturally fade as early. 

One more wader I saw was the greenshank


Greenshank aren't especially common in the UK with a few breeding in Northern Scotland and then a few overwintering here on the South coast. Like most waders they mostly eat small invertebrates but will catch small fish and amphibians. 

I also spotted several oystercatchers


It would be easy to assume that these birds eat oysters but unfortunately their name isn't really very accurate. They mainly eat cockles and mussels but also eat worms, especially if they are inland. Indeed, over the last fifty years more birds have started to breed away from the coast. 

It wasn't just aquatic birds I spotted on the reserve. You wouldn't necessarily expect to see goldfinches on a freshwater marsh but there they were amongst this red plant. 


Also taking advantage of this habitat were a few meadow pipits like the slightly blurry one I captured here. 


These birds are found all over the UK but mostly stay in the uplands in the breeding season. However, in winter they move South to the lowlands and becomes much commoner in the Southern half of the UK. 

I was surprised on my way back to the town through the yacht marina that there were a lot of larger fish right near the shore. 



I wonder why these fish were on the land side of the yacht marina. No fishing is allowed in the marina so they are protected by that and the large amount of human activity and the shallow water means they are protected from most predators. 

I suspect, though I'm not sure, that these are thick-lipped mullet. There are four species of mullet in the UK- red mullet, which these look too dark to be, the golden grey mullet which isn't usually found at estuaries and harbours and the thick-lipped grey and thin-lipped grey mullet. These fish are often found in shallow waters and can even enter freshwater. 

That's all for now, see you again soon!

Sunday 1 October 2017

Arachnids, Butterflies and Crickets

The year is zooming along and it's October already! How did that happen?

I'll start today with a red admiral from last week. Despite the temperatures gradually dropping there are still plenty of these hardy butterflies around.


The results of Butterfly Conservation's Big Butterfly Count were released this week and it was good news for red admirals. Despite the wet summer numbers have risen by 75% compared to 2016. A few decades ago Red Admirals were only summer visitors to the UK- they arrived from warmer parts of Europe in the Spring, bred here and their offspring flew South. Now many overwinter in the UK and the Red Admiral is the most commonly recorded butterfly during the Winter. 

The most commonly spotted butterfly of the count was the gatekeeper and other butterflies which had a better 2017 than 2016 include the comma, the small copper and the common blue. But it was a terrible year for the UK's three species of white butterfly (green-veined white, large white and small white) with all showing amongst their lowest ever totals of the count. This is partly due to the wet summer but may also be because they emerged earlier than usual, before the count begun. Certainly it felt like they were around in large numbers locally. 

Moving on, it's always nice when a more unusual moth finds it's way into the house where you can get a good look at it. This is a light emerald moth


These are relatively common moths which can often be seen in gardens and parks. It's likely this individual is from the second of two generations this year. The green colour fades over time until the moth eventually becomes almost pure white- this is common amongst green moths. 

I've noticed lots more spiders over the last few weeks, many obstructing pathways with their webs. 



These are both garden spiders, easily identifiable due to the cross of white spots on the abdomen. Spiders catch their prey in a variety of ways but this species does so in the one most familiar to us- they spin orb webs and sit in the middle of them waiting for insects to fly into the web. 

Spider webs are incredible feats of nature. The tensile strength of spider silk is greater than the same weight of steel and has much greater elasticity. It's also thought that webs are electrically conductive which causes the silk threads to spring out to trap their quarry- flying insects tend to gain a static charge which attracts the silk.

Another recent invertebrate sighting was this cricket which I think is a roesel's bush cricket


Interestingly, a small number of this species are 'macropterous' which means they have much larger wings than normal. In most populations it's about 1% of individuals but some populations have higher numbers. It's thought that this is a dispersal technique. The idea is that in well-established populations or in strong seasons the population becomes dense so macropterous crickets can fly further to an area where there are less crickets and therefore more food. 

That's all for today but I'll leave you with the bright red leaves I always love to see at this time of year at the corner of my street.