Conservation Manager, Stuart Benn, with a roundup of his season on the hills.
No, not the Radio 4 chat programme nor the 1980s R&B group but time for an end of season tie up of some threads left hanging from previous blogs.
I always get mixed feelings at this time of year when all the surveys have been done – relief as it marks the end of a really busy time but sadness too as it marks another hour of the clock ticking by. Each year, I make sure I get out as much as I can and I’ll keep doing that whilst I’m still fit and able for “summer’s lease hath all too short a date.”
To begin at the beginning, my very first blog was about planting for insects – little did we know back in mid-April that we were set for a cool, wet spring and summer, one of the worst on record for butterflies. But, just in the last few weeks as it’s warmed, Small tortoiseshells, Peacocks, Small whites and Speckled woods have come out and made straight for the pollen. Hornets, hoverflies and bees didn’t seem to be as bothered by the weather and right from the start made a bee-line for the flowers - so much so that the garden can be heard just as much as seen and smelled. I get real satisfaction from knowing that those insects wouldn’t be around us without those specially chosen scabious, bugloss and the like. Talk about getting a buzz!
Small tortoiseshell butterfly
At the weekend I was taking a look around some of the glens that I’d done Ring ouzel survey this year – very quiet and all I saw was one fledged youngster where before the air had been filled with their ringing songs and most seem to have now headed south en route to their winter home in Morocco’s Atlas Mountains. But the surveys went well and, in the end, my four areas produced 0, 2, 6 and 7 territories so in the Monadhliaths, at least, they seem to be doing just grand and it’ll be fascinating to see how my figures fit into the national picture.
Last week also saw the final trip to the Common scoter lochs and gave a very disappointing lack of any adults or young – lots of work still needs to be done on what’s going on here and how it can be turned around. In my previous blog on the scoters, I talked about trialling different count methods (from land/boat, from the air and taking aerial photos) – looks like the land/boat counts are by far the most accurate though we may do another trial ‘cos, if we can get the air surveys to work it’ll save a lot of time and money too.
I’ll come back to Slavonian grebes in a future blog as there’s lots to say and there’s still no word on when the divers or eagles are going to be on the One Show but we’ll let you know as soon as we do! But I can say that those eagle chicks are doing well and have flown the nest – I took a wee look at them a couple of week’s back and they’re looking good!
Prime Ring ouzel habitat.
But I’ll finish this short look back with my two stand-out moments from some great memories of the 2012 season. The first was in early June when I was out ouzel surveying and taking a wee breather. When I’m in hill country I make a habit of scanning ridges just to see if anything is about. On this occasion, I picked up a young pair of eagles some 5 kilometres away and the male was doing a bit of display which consists of a series of steep dives. I kept looking through the binoculars and followed them as they came towards me – how quickly and effortlessly they covered those kilometres! Before long they were looking pretty big in the bins –no wonder, they were right above me! Then, and I’m sure the bird did it for fun, the male started displaying by stooping right towards me before pulling up (still a couple of hundred metres above me) and then starting over again. The sight of an eagle heading right towards you at speed is quite a thrill and not something I’ll forget in a hurry!!
And my second top moment was just at the weekend there. I was almost back at the car after a few hours on the hill and noticed there were a lot of Black darter dragonflies about. Rather than just walk by, I stopped and watched them for a wee while. The way the sun glinted off their wings and turned them to molten copper was just beautiful and every bit as arresting as that displaying eagle.
So, just two of mine - I wonder what your favourite moments with nature have been this year?
Ever wonder how the thousands of seabirds that visit our coasts each summer are counted? Doug Gilbert, Head of Reserves Ecology, gives us some insight.
Counting seabirds: Start at 1 and keep going
Counting seabirds – start at 1 and keep going! All very well but how do you keep track of numbers in a vast colony on a vertical sea cliff? Well there are a number of different ways depending on the colony size and habitat and most importantly the species that you are counting.
Cliff nesting birds that build obvious nests, for instance kittiwakes, gannets and shags are relatively easy. By counting the number of “Apparently Occupied Nests” or AONs in the trade, you can easily estimate the number of pairs on the cliff. In very large colonies you might only count a small plot on a regular basis to give an indicator of how numbers might be doing in the rest of the colony.
Kittiwake and shag by Andy Hay (rspb-images.com)
Guillemots don’t build any nests although they do defend a small section of cliff ledge as a territory. The best way to estimate the numbers in a consistent way which can be repeated year after year is to make several counts of all the individual guillemots present over a period in early to mid June. This is when adult attendance at the colony is at a peak. The number of individual birds present is then averaged, or a best estimate is made if the weather or other conditions make some counts less reliable. Converting this into an estimate of pairs rather than individuals is a bit less reliable than counting AONs but we can still compare numbers over time to look for declines or increases. Razorbills are counted in the same way but they are often hidden away in rock crevices on the cliff so are more difficult!
OK, but what about puffins? They lay eggs and rear their young at the end of a burrow which you can’t see in to! To make things worse, lots of puffins that are not breeding visit colonies and hang around getting their pictures taken by visitors. How do you find out whether the breeding numbers are changing? The technique is not easy but it is possible with patience and skilled observation. By using photographs of sections of the colony and marking burrows that are being used regularly by puffins carrying fish, you can estimate how many burrows are occupied by breeding pairs in any one year (Apparently Occupied Burrows or AOBs). Over several seasons it is possible to follow trends in numbers in a particular colony or area. This does take a lot of time though and is only done in a few places where counters are available.
puffin by Andy Hay (rspb-images.com)
Right then, what about storm petrels and manx shearwaters – not only do they breed in burrows but the non-incubating adults only visit at night! Monitoring the numbers of these birds is extremely tricky and the best technique we have involves playing a tape recording of the species concerned at the entrance to their burrows and recording how many birds respond to the call. We know that not all petrels in burrows respond so working out what the numbers mean is a matter of statistics based on average response rates – and get this – each colony might have a different response rate! So using a response rate from one colony might not give you a very good estimate at another. Male and female petrels also have different response rates so it gets even more complicated!
Many gulls and skuas nest on moorlands on the ground so surveying them is often a matter of watching from a vantage point and counting the numbers of territories you can see using the birds behaviour as clues.
Arctic skua chick by Andy Hay (rspb-images.com)
Counting seabirds can be smelly, exciting, cold and intriguing work but when you are back at the office and you can add a dot to a map or a point on a graph showing this years results, it all makes it worthwhile.
Counting seabirds has never been so important a task as it it is now. With many seabirds in real trouble, all that effort by hundreds of people over the years across Scotland gives us the raw data that we need to show politicians the desperate need for better management of the marine environment, including the designation of Marine Protected Areas (MPAs), and more action on climate change.
Brand new blog from Conservation Manager Stuart Benn.
No blog from me last week because I was well away from my usual habitat - travelling round the south of England on a fact-finding tour. The idea behind the trip was to meet up with RSPB staff and talk to them about how they go about their jobs. The Scottish Highlands and, say, East Anglia could scarcely look more different yet the principles of conservation and communication are the same and it’s good to pick up fresh ideas and think how they can be applied back home.
No need to go into any of the details of the chats here but, instead, I’ll just highlight a couple of places that made a big impression.
First up were the RSPB Reserves at Lakenheath Fen (near Cambridge) and Ham Wall which sits on the Somerset Levels under the shadow of Glastonbury Tor and which is twinned with the Shapwick Heath National Nature Reserve next door. A visit to any of those places in 1995 (during the heyday of Britpop – Pulp and Oasis were amongst the headliners at Glastonbury) would have revealed either carrot fields or worked-over peat diggings with a distinct lack of wildlife. But, since then, those places have been taken on and managed by conservation organisations and the transformation has been nothing short of monumental.
The main form of management has been to get water back on site and then let either nature take over or give it a helping hand by planting reeds and such like (these words do not even hint at the level of work that this entails!). Today, these are fantastic wetlands – the home of cranes, bitterns, otters, dragonflies, egrets and hundreds of other species. As a testament of what can be achieved with a lot of vision and a lot of work, I can’t think of better examples and they are truly inspirational places to visit.
The other wonderful places that we took in were the chalk grasslands at Denbies Hillside (a National Trust site near Dorking in Surrey) and the Dorset Coast between Durlston and Lulworth (owned and managed by the County Council and a private estate, respectively).
These were alive with butterflies – Chalkhill blues, Silver-spotted skippers, Lulworth skippers, Gatekeepers, Walls, Marbled whites and a dozen or more other species. The variety was great to see but it was the numbers that got me – clouds of them flitting over the hot turf and I’m sure I saw more butterflies there in a couple of hours than I have ever seen in total in my entire life. Absolutely magical.
We need more oases.