Category Archives: Birds

Bird Nerd part 3: feeding habits

As I mentioned in my last bird nerd post, I have quite a lot of data on the birds that visit my garden, and am keen to hear ideas for questions I could look at with it. Someone suggested that it might be worth looking at whether birds with similar feeding habits have similar patterns of visits over the year. So I gave it a go.

First I tried to work out how I could group my avian visitors, and settled on the following categories:

  • those that feed from the seed feeder (house sparrows, great tits, chaffinches)
  • those that feed from the suet pellet feeder (blue tits, coal tits, black caps, long-tailed tits)
  • those that eat seed from the table (wood pigeons, collared doves, feral pigeons)
  • those that eat suet pellets or mealworms from the table (starlings, magpies, jackdaws, crows)
  • those that feed from the ground / other sources (blackbirds, song thrushes, pied wagtails, wren, dunnock, robin)

Of course there is a certain amount of overlap. For example, sparrows and bluetits will feed from both the seed feeder and suet pellet feeder, but do seem to have preferences.

I then created some simple line charts, using the average number of each species seen per observation day for each month of the year, based on data from June 2012 – May 2013. Here are the charts.

seed

suettableseed  tablesuetground

For most of them it looks like the average number seen per observation day is independent of feeding habits. But there may be some relationship for those that feed from the ground or suet pellets or mealworms from the table.

The patterns are unlikely to be driven by changes in the availability of food in my garden, as this is broadly steady throughout the year. However it could be linked to the availability of other food sources beyond my garden. It may be that birds in this category are more influenced by the weather than the other categories, so fluctuations are more in line with each other.

It’s not conclusive evidence, but it’s an interesting hypothesis. When I have time I will use data from the whole 3 years to draw up scatter plots for pairs of birds whose average numbers seem correlated. Can you think of other ways I should test for a relationship? Are there any other questions you think I should look at?

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Top 10 Christmas Present Ideas for Wildlife Enthusiasts

The wonderful Transition Dorking’s Golden Ticket event has got me thinking about Christmas shopping. Here’s a list of my top 10 present ideas for the wildlife enthusiast in your life. Some of them I already have, so can vouch for their brilliance. Others are things I’ve had an eye on for a while, hint, hint!

1) Swiss Army Champ knife: no nature explorer should be without a Swiss Army knife, and this one is all singing, all dancing. I’ve had mine for a couple of years, and can vouch for its robustness and versatility. My one has sawn off tree branches, cut wire to repair nest boxes, removed a tick from a dormouse, prised open paint tins, helped identify which small creatures have opened hazel nuts and performed numerous other essential tasks. My superhero name would be Swiss Army Wife. The only thing that could improve it would be a torch (which I’ve added to mine via the ring). It’s comforting knowing that, should I ever have to remove a stone from a horses hoof, I’m well equipped. Don’t just take my word for it – Simon King swears by his too!

2) Motion-triggered infrared trail camera – this one’s a bit pricier, but very exciting. We didn’t know we had hedgehogs or foxes visiting our garden until we got one of these. Most can be set to take stills or film, and should have a way of adjusting the focus.

3) Animal tracks kit – this is marketed as a stocking filler for kids, but who doesn’t secretly yearn to be a wildlife Sherlock Holmes? It’s on my Christmas list!

4) Camera bird box – give your loved one the tools to run their own Springwatch. We’ve been very impressed with the quality of the camera on ours, and while our bluetits have yet to get their youngsters as far as fledging, it’s still been fascinating to follow their progress each day. Plus when the nest box is not in use you can use the camera for other projects.

5) Mammal tunnel – more wildlife detective gear! Following on the theme of number 3, this simple set-up can help reveal which mammals make use of your garden. I think it would be a good project to do with a child (although don’t expect to find hedgehogs in winter!) or the young at heart. I enjoyed trying ours out, and if your loved one already has a bird box camera it can easily be rigged up (using gaffer tape) in the tunnel.

6) Paramo waterproof trousers – another expensive one, I’m afraid. But for anyone who spends a lot of time out in the Great British weather, these are an excellent choice. Not only do they keep the water out, but they are breathable and well ventilated, so you don’t end up with steamy legs. And they are comfortable enough to wear as normal trousers (rather than over-trousers), so you can just put them on before you set off, and not have to wrestle to get them on over your boots half way up a cliff when it starts raining. Having dry legs makes the outdoors a lot pleasanter on a rainy day.

7) Wildlife books – For the stormy days when not even good waterproofs are enough to persuade you away from the fire, a good selection of wildlife books is essential. General guides are useful for identifying animals, or working out where to see them. As a good, concise guide with plenty of pictures I would recommend the Collins Complete Guide to British Animals For a more weighty tome filled with high quality scholarship Mammals of the British Isles can’t be beaten. Hugh Warwick’s The Beauty in the Beast is an inspiring read, and the British Natural History series is good. On my Christmas list this year is Badgerlands by Patrick Barkham and the new edition of Otters by Paul Chanin.

8) Camera bird feeding station – If your loved one already has a bird box camera, this feeding station can make use of the camera when it’s not spring. I haven’t tried it, but it’s on my list.

9) A hand lens (or magnifying glass) – Hand lenses are very useful for examining things close up. It can help you distinguish what sort of mouse has been nibbling a nut, whose fur has been caught on barbed wire, and give you a better view into the world of insects. Another important tool in the wildlife detective’s kit. Just the pipe and deerstalker hat to go!

10) Courses – there’s so much to learn about wildlife, and good as books and films may be, they can’t rival getting out in the wild with an expert. I’ve been on lots run by Surrey Wildlife Trust and can recommend them. I’ve also had a couple of very enjoyable photography days at the British Wildlife Centre. Other Wildlife Trusts, the PTES, the Mammal Society and the Field Studies Council all run a selection as well – have a look to see if there are any that might inform and inspire your loved one.

I hope this list provides a bit of inspiration. What would you have on your list of gift ideas for wildlife lovers?

Alien invaders 1: Canada Geese

Canada GeeseEach day I walk through the park, past the mill pond, and nod good morning to one particular goose. He’s quite distinctive, with the white marks on his face. He’s the patriarch of the community of Canada Geese on the mill pond. While his many goslings are growing up, he tirelessly watches over them, protecting them. (Unlike the ducks, which take a rather more laissez faire approach to parenting, letting their tiny ducklings zoom off or get left behind.)

Over the years I’ve grown affectionate towards him – you’ve got to admire that kind of devotion. A couple of years ago a tree fell right on top of the nest his mate was sitting on, yet miraculously she and the eggs survived, and together they brought up the large brood. I was rooting them on, each morning anxiously counting the number of goslings to make sure they were still surviving.

Goslings

So it came as more of a surprise to me than it should have, when I learned that they count as an invasive non-native species. I mean, the clue’s in their name: Canada Geese. But I still find it hard to think of them in the same category as Japanese knotweed. According to the GB Non-native species secretariat, an invasive non-native species is any non-native animal or plant that has the ability to spread causing damage to the environment, the economy, our health and the way we live.

So, are Canada Geese a problem? They’ve lived in the UK since they were first brought from North America to St James Park back in the 17th century. But their numbers have increased hugely over the last 60 years, going from 4000 in 1953 to around 89,000 in 2000. They are viewed by many as pests – they make a lot of mess on footpaths in parks, and there are concerns they may spread salmonella to cattle. Canada Geese who are nesting or looking after young can be aggressive towards people (which can be a problem as they seem to like living in public parks, bringing them into close contact with people, particularly children). Their droppings may increase the nutrient content of water, which reduces oxygen content for fish. And around airports there have been problems with damage to planes and people when they collide with Canada Geese. The main issue is they are so numerous…

In fact, in some places the eggs of Canada Geese are treated so they will not hatch, to try and prevent them from expanding even more. So while I was rooting on each of the goslings, should have been hoping the reverse? I try and be fairly unsentimental about my love for wildlife. But I can’t yet find it in my heart to feel anything other than affection for at least this one particular Canada Goose, alien invader though he may be.

Bird nerd part 2: summary stats

So, having collected all this lovely data, what do I know about the birds that visit my garden? Here are some summary stats from the last three years of data collection.

  • In 2010-11 I saw on average 7 different species per observation day. In 2011-12 this went down to 6, and in 2012-13 it went up to 8.
  • In 2010-11 I saw on average 14 individual birds per observation day. In 2011-12 that went down to 12, and in 2012-13 it went up to 15.
  • These averages hide quite a bit of seasonal variation: September is generally pretty quiet, while the bird table is unsurprisingly busy in December and January.
  • The most regular avian visitors to the garden were: bluetits in 2010-11, being seen on 55 out of 64 observation days, starlings in 2011-12, being seen on 35 out of 43 observation days, and woodpigeons in 2012-13, with only one observation day out of 44 when they didn’t make an appearance.
  • The most numerous visitors to the garden were starlings by far (which won’t surprise anyone who has seen hoardes of them descend on a bird table), although in the last year house sparrows have almost managed to catch them up.

    Bluetit
    Bluetit gathering nesting material

Changes in which species visit over time

As I mentioned in the first ‘Bird nerd’ post, altogether I’ve seen 26 different species of bird in the garden, although never all in the same year. In 2010-11 I saw blackcaps on 15 observation days (in the winter), but only once in 2011-12 and once in August 2012-13 (which is a shame, as they are pretty birds).

There have been no records of jays since 2010-11, but even then they were not frequent visitors. Other birds missing in 2012-13 that I have seen (infrequently) in other years include crows, greenfinches and siskins.

On the bright side, in 2012-13 I saw chaffinches and some kind of warbler for the first time. It’s quite encouraging that 4 years after moving here we’re still spotting new species.

Future analysis to be done

The few stats I’ve presented here are only the tip of the iceberg in terms of what I could examine from my data. One question I would like to look at is how the weather affects bird numbers. I’ve got very basic data on weather for most observation days, but only as far as whether it was sunny, snowy, rainy or overcast. Since we had solar panels installed last June I now have data on sunlight. My theory is we get more bird visits on sunny days than rainy or overcast (controlling for the month of the year), but we’ll see if the data supports that…

Let me know if there are any other questions you would like me to look at – for example, if you’re interested in a particular species or comparison over time…

Amateur ecology

Over the last few years I’ve been doing quite a lot of reading about wildlife, as well as going on courses. One of the biggest surprises I’ve had is there’s so much we don’t know, even about some of our most familiar species. For example, we don’t really know what water voles do all winter, or where basking sharks go. Linked to the realisation of how much we don’t know about our wildlife, is the discovery that normal people, like you and me, can make a meaningful contribution to scientific research about wildlife.

The other day I read, in Hugh Warwick’s book The Beauty in the Beast, about Denis Summers-Smith. It was inspirational. Denis is a mechanical engineer and an amateur birdwatcher, who has written five books and over forty scientific papers on the house sparrow. He has discovered many things about house sparrows, including that they mate for life. And all this has been done in his spare time…

For those of us not quite ready to write a book based on our own discoveries, there are many citizen science projects that rely on the contributions of hundreds (or thousands) of volunteers to gather data from across the country. The commitment and expertise involved varies considerably.

For example, each year in January the RSPB run the Big Garden Birdwatch. Almost 590,000 people took part in it in 2013. This involves spending an hour counting the different types of birds that come into your garden on a specific weekend. From this, they can analyse the data from across the country, and spot any significant changes in the bird population. This is important to inform conservation work.

Many other organisations run similar surveys. This BBC Nature article contains a good list.

At the other end of the spectrum, the National Dormouse Monitoring Programme is rather more indepth, requiring trained and licensed volunteers to carry out box checks each month (except over winter). The data collected from this programme is providing new insights into these lovely creatures. At a dormouse conference I attended a couple of years ago, it was very exciting to hear scientific presentations based on data that I helped (in a very small way) to collect. We now know much more about this species than we did before the programme started.

Like many girls of my generation, I gave up studying science after I finished my GCSEs, despite getting my best grades in science and maths. I didn’t think science was for me. I didn’t realise how exciting science could be, and the range of things it could involve. It has been thrilling to learn, somewhat belatedly, that science is for me, and I can contribute to finding answers to questions about our native wildlife. These answers may help us better protect our beautiful and vulnerable creatures, for this generation and those to come.

House sparrow explosion

House sparrows have been fairly regular visitors to our garden. We see them all year round, with an average number of 3 per observation day. But in the last few weeks the sparrow population in our garden seems to have exploded. Before September this year, the most we’ve seen at one time was 9. Now there are more than I can count (they keep moving!).

They’ve been hanging around our garden quite a bit, and getting through the bird seed faster than I’ve ever seen before. I’ve no idea why we have had the sudden increase. In previous years there hasn’t been a large increase in numbers around this time of year.  Perhaps they’ve had a particularly good breeding year?

They’re not the most spectacular of birds, but it’s great to see so many of them, as their numbers have plummeted in recent years. In the 1970s there were around 12 million pairs in the UK. Now there are between 6-7 million pairs. The good news is, data from the British Trust for Ornithology suggests that the decline has stabilised. Now we just need to work out how to help them recover.

Earlier this year we installed a sparrow terrace (to try and tempt them away from our gutters as a nest site). The boxes weren’t used this year, but hopefully some of our new visitors will decide they’re a good nest spot for next year. I’ll let you know!

Have you noticed anything similar in your garden?

Bird nerd part one: a confession

I have a confession to make. I am the garden bird equivalent of a trainspotter. For the last three years I have not only been watching birds in my garden, but recording details of the numbers of individuals of each species I see.

Each day that I work from home I keep an eye (and ear) out for birds in the garden, and record the maximum number of individuals seen at the same time from each species. Over the last 3 years I have clocked up 153 days worth of observations, and lots of completed forms.

Bird observation forms
Some of the completed forms…

While I appreciate that this makes me seem slightly obsessive and sad, it also means I have lots of lovely data to play with. This allows me to monitor trends over time, and see how changes in the garden, weather and seasons affect my feathered visitors.

This behaviour came as a surprise to me. I’ve always considered myself more of a mammal person than a bird fan. I saw birds as nice, but a bit dull (unless they were spectacular kingfishers or powerful birds of prey).

Then we moved house and got a garden. I don’t know when I changed my mind, but soon after moving we installed the bird feeding station, and waited for our first feathered visitors. And waited. And waited.

We had to wait almost a month before we saw the first bird in our garden. Our first visitors were a pair of collared doves. Then more and more types of birds started visiting. Something clicked, and I realised that the garden birds were wild creatures I could watch from the comfort of my own home. And they had their own characteristics. And I could watch real life mini dramas being played out in front of me.

I’m still not sure where the urge to obsessively keep records comes from. I think it must be from working with statisticians for too long. And the transformation is not complete – real twitchers wouldn’t consider me as one of their own. I don’t travel the country in the hope of seeing a rare small brown bird. I’d still choose a glimpse of otter or badger over the rarest of feathered migrants any day.

But I do enjoy watching the birds in the garden. Observing a species we’ve never seen in the garden before makes my day.

Having got that confession out of the way, I’ll try and share some of my observations with you in future posts…

Welcome to the Wild South!

To start my blog, I thought maybe an introduction to my wildlife garden might be in order. We (Dr C, Fat Cat and I) live in a small town, and have a small garden (about 7.5m by 7.5m). Since we moved in (back in 2009) we’ve been gradually trying to turn it into a haven for bugs, birds and other beasts, and have had more success than I anticipated.

The RSPB have some brilliant resources for making homes for wildlife, and many of the ideas we’ve used have come from that.

When we moved in, the garden had a couple of decked areas, a lawn, a couple of borders and a small box hedge. A rampant buddleia has been an attraction for butterflies, bees and birds. Since then we’ve added a bird feeding station, a barrel pond, a small area of meadow, a hedgehog house, birdboxes, some small trees in pots, a wood pile, a raised vegetable bed, an insect log, a bird bath, and probably some more things I’ve forgotten.

Since then we’ve seen 25 species of bird in the garden, along with hedgehogs, a fox, mice, a slow worm, frogs, various pond life and numerous insect species. It’s been really satisfying seeing how quickly wildlife starts to make use of the things we’ve provided. Watching the garden has been a real source of pleasure to me, and I’ve learnt a lot along the way.

The meadow
The meadow
Raised bed & buddleia
Raised bed & buddleia
The mini pond
The mini pond
Bird feeding station
Bird feeding station