Saturday, 20 June 2015

Rockabill Roseate Record broken!! (...and we need 20secs of your time...)



So, we won't know the final figures until the end of next week, but we have some exciting news - We've already broken the record for the number of breeding Roseate Terns on Rockabill!!! Last year's record total was 1250 pairs, but we already have over 1300 nesting here at the moment!


This is fantastic news as Rockabill is the biggest colony of Roseate Terns in Europe. We have around 80% of the north-west European population of the species, so their success at Rockabill will help safeguard their future in this part of the world. As usual, nestbox uptake is very high, with many others nesting in the shelter behind, beside or between boxes.



This fantastic news is down to the hard work put in by a long list of people over the years, but we also have to mention another very important contributor - the EU Birds Directive. Rockabill is a 'Special Protection Area (SPA)' for Roseate Terns amongst other species, since such important numbers breed here. This designation essentially means no damage can be done to the site that might negatively impact their numbers. The Birds Directive also ensures successive governments make the conservation of our wild birds a priority, for example by providing funding for the Rockabill project through the NPWS. Unfortunately, the Birds Directive is under threat, despite doing so much through the years..........


BirdWatch Ireland has launched a campaign to defend the Birds and Habitats Directives - probably the most important campaign we have ever done. You can help by signing the petition at this link. It takes 20 seconds to fill in first name, last name, email and hit submit:

 http://www.birdwatchireland.ie/Supportus/SaveourNature/tabid/1461/Default.aspx



 

If the Birds and Habitats directives are weakened, it will mean that our Irish Nature laws will be weakened, and our wildlife and habitats will suffer. Rockabill is a great example of the effectiveness of the Directives, but they protect a number of other Irish seabird sites, as well as many of the rivers and lakes used by birds and wildlife in the summer and winter. 


Another example is the Corncrake, which has been saved from extinction because of these laws. Small populations of this once wide-spread bird are beginning to come back in the west and north-west of the country. 

And there are many more benefits.

The European Commission has been tasked by its President Jean-Claude Juncker to undertake a review of the Directives with the possibility of merging them. We believe, (as does BirdLife International, World Wildlife Fund for Nature, and the European Environment Bureau along with eNGOs all over Europe) that this is in fact an attempt to weaken the Directives as the push is for economic growth at all costs. As part of the Review, the Commission must undertake public consultation and in this case it is in a form of a questionnaire. Along with BirdLife International etc we are asking people to sign the petition/questionnaire that we have developed which has all the answers filled in already that are most supportive of the Directives.

 It takes 20 seconds to fill in first name, last name, email and hit submit.

http://www.birdwatchireland.ie/Supportus/SaveourNature/tabid/1461/Default.aspx



Wednesday, 17 June 2015

New Arrivals on Rockabill!

Our first Tern chicks have hatched!!

Last weekend we finally had our first hatchlings - Black Guillemot and Oystercatcher chicks (blog post on it here). Unfortunately the Oystercatcher chicks were attacked by nearby adult Common Terns and didn't survive, but on a brighter note we now have 10 Black Guillemot nests with chicks, and another 40 or so to come over the nest few days and weeks!

Black Guillemot chick. (Picture taken under NPWS license)

...which will grow up to look like this eventually! (Picture taken under NPWS license)


With the knowledge that Tern chicks take around 23 days to hatch, and the fact that we found our first few Tern eggs around 23 days ago, we've been on high alert to find the first Tern chicks.  Once they hatch we have to weigh and measure a subset of them every day, as well as ring them and track their survival. This morning we saw our first Roseate Tern egg 'pipping' - i.e. the chick was starting to break out, and by this evening we had four tiny Roseate Tern chicks as well as three Common Tern chicks!


A Roseate Tern chick on 'Day Zero' i.e. the day it hatched. (Picture taken under NPWS license)


Common Tern chick on 'Day Zero'. (Picture taken under NPWS license)
Two Common Tern chicks from above - well camouflaged against the ground. (Picture taken under NPWS license)

Common Tern chick. (Picture taken under NPWS license)

Chicks of both species tend to sit fairly still for their first day or two - not venturing out of their nest scrape. After that the Common Tern chicks will be running all over the place, whilst the Roseate Tern chicks will stay hidden in their nestboxes or in the nearest bit of shelter they can find. They'll grow very quickly over the next four weeks, changing shape, appearance and behaviour until they're finally able to fly. We'll do a blog post later in the season to illustrate the changes they go through.

As well as that exciting news, we've also been doing the first part of our nest census over the last two days - counting every nest on the island to establish how many breeding pairs of birds we have - and we've already broken the previous Rockabill records for two of our five species!! And we havn't even done the second part of the nest census yet!

Stay tuned later in the week for details!

Sunday, 14 June 2015

Two sets of two chicks from two species in two days!


We've been on Rockabill a bit over a month, the weather is picking up and we're now getting into the main part of the summer. That can mean only one thing - chicks!!

The first eggs we found on Rockabill this year was a clutch of two Oystercatcher eggs. They don't usually nest on the Rock (they usually nest on the Bill and quickly get predated by Gulls...), so we weren't sure how they'd get along with the presence of both wardens and Terns.

Oystercatcher incubating two eggs. (Picture taken under NPWS license)


We were keeping an eager eye on the eggs over the last week, expecting them to hatch, and it got to a stage where we thought it might have been too late and the eggs had failed......but then on Friday evening we noticed two tiny bills, complete with small white egg-tooths, poking their way out of each egg.....

Oystercatcher eggs 'pipping' - the chicks small white 'egg-tooth' is visible, helping it to break out. (Picture taken under NPWS license)

......And on Saturday morning two Oystercatcher chicks had hatched. Unfortunately, one of the chicks died this morning after wandering away from the nest and encountering some aggressive/defensive Common Terns. We knew there was a risk of this as the Oystercatchers nested in the middle of the colony. Had they nested somewhere on the edge they would have benefited from the protection of thousands of Terns while still minimising the risk of chicks getting into trouble with the Terns. There is still one chick though - hopefully the parents can supervise and protect it and it will survive the summer.


An Oystercatcher chick - note the colours that camouflage them well until they're able to fly. (Picture taken under NPWS license)

The species we usually expect to lay eggs first out here are the Black Guillemots. As with the Oystercatchers, we knew they incubate their eggs for a bit under a month, and sure enough, right on queue we had our first Black Guillemot chicks on Friday - around half a day before the Oystercatchers! They're just small balls of black fluff at the moment, staying put in their nest-holes, but they'll grow quickly over the coming weeks!


Black Guillemot eggs in a nestbox. (Picture taken under NPWS license)
Our first Black Guillemot chicks of 2015 - sitting safely in the back of their nestbox. (Picture taken under NPWS license)

Black Guillemot chick. (Picture taken under NPWS license)


So there you have it - two sets of two chicks from two species in two days! Unfortunately one of the Oystercatcher chicks didn't make it, but hopefully its sibling will, and fledging success is usually quite high for Black Guillemot chicks here, so that's cause for optimism too. 

Roseate tern chicks take around 23 days to hatch - and it was c24 days ago when we found our first Roseate Tern egg....so keep an eye on the blog either tonight or tomorrow for news on that front.....things are about to get busy out here!!

Monday, 8 June 2015

Variety is the spice of life!


"So what do you actually do out there?" - Like I said before, this is one of the most common questions we get about working on Rockabill- the term "warden" can seem a bit vague! At the start of the season it was all about habitat management and getting the island ready to host as many nesting Terns as possible. Since the first eggs were laid we've been doing twice-daily nest-checks of a number of sub-sections of the island. We'll be checking these every morning and evening between now and when we leave at the end of the summer, so we'll know every little detail about the timing and number of eggs laid, the hatching success and growth of the chicks, and ultimately whether those chicks fledged and the nests were successful. 

At this part of the season we check our study areas for new eggs, twice a day - some are in nestboxes, others outside them.


Spending a couple of hours each day checking nests of thousands of Tern species, you see a lot of eggs!! (understatement alert!) This period is arguably less interesting/fun than when we have chicks running around the place, but the eggs are interesting too. Common Terns lay eggs on patches of bare ground, and so their eggs follow the same basic pattern of most ground-nesting birds eggs - they're coloured to match the ground as closely as possible, with a series of spots, streaks and blotches that help break up the outline of the egg against the ground - so any aerial predators (Gulls, Crows) will have difficulty seeing them and hopefully pass them by. If you take a plain coloured/patterned chicken egg and put it on bare soil, gravel or shingle, you'd have no trouble seeing it from a distance, and knowing that it was an egg too. The Common Tern eggs you'll see below are usually much harder to spot until you're right up next to them.

In a colony like this where you have >2,000 pairs of Commons nesting there's considerable variation in colour and pattern style of eggs. Commons out here nest on bare rock, soil, on top of vegetation, on top of dead vegetation etc. - all of which are different colours, and so the population here needs to be able to cope with that. Essentially, it's a numbers game, as evolution so often is! There's huge variety in both the eggs they lay, and the substrate they lay on, so there'll never be a year where all of the eggs are easily found by predators - at least some (usually most) will successfully last long enough to hatch chicks, who themselves are well camouflaged too. A good proportion of chicks survive, and come back in future years to breed, they lay a large number of eggs with various camouflaged patterns, and the cycle continues!

So here's a sample of the variety in Common Tern eggs that has served them so well over the years:

(All pictures taken under NPWS license - never take pictures of nests or eggs without one!!)


Colours:

Most of our Common Tern eggs are this green-y colour, with brown/black spots and blotches.

....some are a lighter shade, with spots more concentrated at the bottom end.....
...there are also plenty of brown eggs like these. Note that these eggs are more pointed at the top end than those pictured above!
We also get a few like this - bright blue!


 Patterns:

Some are spotty all over, others more blotchy.....

.....some have the spots/blotches concentrated at one end....

....or occassionally across the middle......

Shape:

Most Common Tern eggs are a 'normal' egg shape, but there's always a few exceptions....

Occasionally we see some that are more pointed than average (like Roseate Tern eggs), and some shorter and more rounded.

Just Plain Weird.....:

In a colony of thousands of nests, and even more eggs, we see a few that havn't formed right and are generally infertile. In many cases the adults realise this soon after laying and roll them out of the nest, so that they can concentrate their efforts on their other eggs.


This white egg has a thinner shell than normal and so is fragile and prone to cracking. 

This unusual egg is longer and narrower than normal!

The third egg here is tiny compared to what it should be!
This one was close to being normal.....but then ended up being the weirdest one we've ever seen!

Thursday, 4 June 2015

Rockabill Roseate Terns on BBC Springwatch tonight!

Our Roseate Terns will be on BBC Springwatch tonight (4th June) - BBC Two 8-9pm. So set an alarm, stick the kettle on, and get a glimpse of the sights and sounds we're lucky enough to be surrounded by for three months on Rockabill!

Let us know what you think on the Birdwatch Ireland facebook page!

Roseate Tern (picture taken under NPWS license)

Roseate Tern (picture taken under NPWS license)

Roseate Tern (picture taken under NPWS license)


Roseate Tern (picture taken under NPWS license)

Monday, 1 June 2015

Rocka-blitz!



Last week we had our own mini-bioblitz on Rockabill! To mark 'International Biodiversity Day' on May 22nd, the National Biodiversity Data Centre invited people to spend some time over the weekend recording the wildlife in the garden, locality or nearest wildlife site, and set a target of 50 species per individual with the hope of receiving 1,000 records per day. Now it just so happens our garden, locality and nearest wildlife site are all the same thing at the moment - the small island of Rockabill, and both being Zoology graduates we liked the idea of learning a bit more about what biodiversity we share the island with. And before anyone asks we didn't count birds in our 50 species - we felt that would be cheating! Or Andrew did at least......

Rockabill, in all of its uniqueness, has a mix of flora and fauna that you would find on rocky intertidal seashores, coastal habitats and your average garden or house - don't forget this was home to the families of the lighthouse keepers for many years, who grew their own vegetables and planted flowers and hedges out here. Like I said, unique!

After much hard work we managed to break the 50 species target! There are definitely species we missed (you'd be surprised how many different types of seaweed there are...), but here's what we got....


You'd be surprised how many plants and animals you can find in even a small rock pool like this - just spend some time, and get a closer look!


Rock Pool Fauna and Fish
1. Common Limpet
2. Dog Whelk
3. Blue/Common Mussel
4. Beadlet Anemone
5. Acorn Barnacle
6. Common Sea Urchin
7. Common Starfish
8. Common Shore Crab
9. Common Blenny
10. Sandeel
12. Pollock
13. European Sprat

Common Limpet and Acorn Barnacle

Sandeel (a.k.a. Tern food!)

Spot the Blenny! (A. Power)


Seaweeds
14. Bladder Wrack (Fucus vesiculosus)
15. Harpoon Weed (Asparagopsis armata)
16. Kelp (Laminaria digitata)
17. Sea Lettuce (Ulva spp.)


Marine Mammals
18. Harbour Porpoise
19. Grey Seal
20. Common Seal

Harbour Porpoise (A. Power)

Grey Seal


Plants
21. Tree Mallow
22. Sea Campion
23. Mayweed
24.Scurvy Grass
25. Hottentot Fig
26. Common Dandelion
27. Prickly Sow Thistle
28. Blue Heebee
29. Sea Beet
30. Rock Sea Spurrey
31. Sorrell

Tree Mallow - it's quite pretty when it's not completely taking over the island.....


Invertebrates
32. House Spider
33. Garden Spider
34. Woodlouse Spider
35. Garden Snail
36. Common Garden Slug
37. Earthworm
38. Common Centipede
39. Common Woodlouse
40. Common Earwig
41. Ground/Black Click Beetle
42.  Fruitfly
43. Bluebottle fly
44. Sandhopper
45. Landhopper

Garden Tiger Moth larva

Common Quaker Moth larva

Ichneumon Wasp


46. Green-veined White
47. Small White
48. Peacock Butterfly
49. Garden Tiger Moth
50. Common Quaker Moth
51. Ichneumon Wasp (Pimpla spp.)
53. Buff-tailed Bumblebee (Bombus terrestris)



Overall we felt it was a great initiative from the National Biodiversity Data Centre that gave us an excuse to find out more about what species we share the island with - as well as highlighting some species groups we need to brush up on...

If we can find 50+ species in a day on a small, isolated patch of land like this then it should be easy to get the same amount of species in most gardens up and down the country - so get outside and get looking! Don't forget to submit your records too, and  that it's just as important to record the common species as the more unusual ones!