The Crunching of Carapace

The final Little Tern chick of the Kilcoole season hatched on Monday 22nd July. It will be metal ringed soon, bringing the total to 248 and a further 126 green darvic colour rings applied to the right tarsus of captured chicks will identify these birds as having been born at Kilcoole. Our next duty is to ascertain, to the closest possible account, what proportion of the chicks fledge successfully and to do our best in making sure the percentage is high.
To provide the highest level of protection to Little Terns and their chicks at Kilcoole beach, wardens are present around the clock. This means three wardens, each on sentry duty for eight hours a day. Shifts are divided into morning, evening and night and are rotated occasionally to afford the wardens some variety, whereby the wildlife encountered can vary considerably at different times of the day and night. The morning shift is a marvellous time to experience birds embracing the new day, boldly staking a claim to their territory through their dawn chorus of song. The evening shift, which encapsulates the local celestial meridian, is the best time to encounter heat loving invertebrates such as bees, butterflies, dragonflies and damselflies.

Birds of the dawn chorus (from top left: Goldfinch, Sedge Warbler, Yellowhammer)

 As the sun retreats and the birds and butterflies abate, a dusky calm descends on the beach and over the lagoon. Gulls and corvids depart the mudflats having foraged contently all throughout the low tide. The chirping of Little Terns recedes, until; silence. Then, an Oystercatcher calls out in it's distinctive trill in typical defiance to the end of the day.

Night has fallen...

I have finished my evening shift. It is now 23:05 and I venture out once again to become a part of the nocturnal wildlife. I have a bat detector in hand and hopes are high for some encounters, due to the warm, calm night. All at once the tiny fluttering silhouettes of bats surround me, resonating at 55KHz on the heterodyne detector, Soprano pipistrelles. With a foraging range up to 3km, they have most likely travelled from a roost in the broadleaved woodland across the lagoon to the west. I retune in the hope of detecting a Leisler's bat, the Irish population is of international importance and the species has been recorded at this location in the past but to no avail.

Pictures above: top left; Four-spotted chaser, top right; Common Blue, bottom left; Small Tortoiseshell, bottom right; Drinker moth caterpillar.

Then suddenly, from within the lagoon, a ripple accentuated by the moonlight and the silhouette of a swimming mustelid comes into view. It navigates into the shadow of the shore, in close proximity but out of sight.. then.. from the other side of the earthen bank.. the crunching of carapace! I retreat with haste to get a torch, feeling certain that another encounter with a mink is looming. Shining the light down from on top of the bank where I am now standing, homing in on the noise, illuminated, chewing, a mustelid indeed, an Otter.

It's great to see an Otter in the lagoon for the first time this season, not least because they will repress the number of mink in the area (Bonesi, 2004) but also because their playful nature and social habits are a joy to watch. Fingers crossed that they hang around.

Bye for now,

Darren.

Reference, Bonesi, Laura & Chanin, Paul & Macdonald, David. (2004). Competition between Eurasian otter Lutra lutra and American mink Mustela vison probed by niche shift. Oikos. 106. 19 - 26. 10.1111/j.0030-1299.2004.12763.x.

The Battle for 300

Nothing occurs in nature

except the impossible 

and that never occurs - Gallileo Galilei

Friday 12th July and an air of cautious exultation has descended as the 240th Little Tern chick at Kilcoole receives it's uniquely coded metal ring that will accompany it, ad infinitum. With the population of chicks now well into it's 3rd century for this year, the feelings of exuberance at reaching this noteworthy milestone, are perhaps over-zealous. After all Little Terns have been recreating this scenario for centuries, if not millennia, on coastal stretches here and abroad, minus the metal rings of course! Many bird species have developed the evolutionary gambit of relaying in the event of a nest failure, it is a strategy that is certainly critical to reproducing successfully. Nonetheless it is difficult not to feel great respect for such a display of resilience and resurgence in the face of adversity and great challenges and it is difficult not to feel somewhat invested in the outcome of the colony.

The 240th Little Tern chick ringed at Kilcoole in 2019

As the number of hatchlings and subsequent fledglings (currently 15) continues to proliferate, the number of active nests inevitably dwindles. Of course this is by no means the end, it is just the beginning! The previous threats to eggs posed by high tides and hungry hedgehogs have lost their potency due to the newly found mobility of this years offspring, but the danger has not abated. Developing lean chicks provide calorific fare for hungry ground predators and attacks from the air. While foxes and crows mean you don't dare to blink, don't ever forget about the wiley old mink!

Now mobile Little Tern chicks march up the beach at Kilcoole

Fledgling success, preparing for a first trip to Africa

The myriad of challenges certainly causes a degree of stress to the Little Terns and don't forget that they have navigated about 4,000 km to arrive here and soon they will experience the innate sense to make the return journey to wintering grounds in West Africa. However, the majority exude confidence and knowhow, as if they have done it all before! Well this is very much the case. Only this week we received news from our neighbouring colony in Gronant in north Wales, that a Little Tern had been re-sighted there, that was ringed in 1993. Fit and healthy at 26 years old this is now the oldest Little Tern on record. Astounding! The previous record was 21 years. Such a symbol of courage against overwhelming odds could be likened to the Battle of Thermopylae, exemplified as the power of a patriotic army defending it's native soil, or in this case shingle and sand! We are delighted to think that our Irish Little Terns will be going back to Africa with their ranks bolstered by 240 and we will continue to fight in The Battle for 300!

THIS IS STERNA!!

Adult Little Tern defending territory

Sunset over the North lagoon

All for One and One for All

Help from volunteer wardens has always been an important part of the success of Kilcoole Little Tern Project. For this week’s Blog we welcome a contribution from Eilis who worked with us for four weeks. Having just completed a BSc. in Applied Freshwater and Marine Biology at GMIT Galway, Eilis had just the right range of skills to become a great asset to our team. Previously Eilis has volunteered and completed internships with sea turtles and penguins. She says, “I have always wanted to work in seabird conservation and I was delighted when BirdWatch Ireland accepted my application to join the team in Kilcoole, I was excited to join the project and learn all about Ireland’s rarest breeding seabird and the challenges involved in protecting them.” 

View west from the hide (photo Eilis Hogan)

“Thinking back on the day I arrived on the Kilcoole project I was completely blown away by the beautiful scenery, the wildlife and how peaceful this part of the country was considering how close it is to Dublin City”.

“That morning I joined Darren in the hide where I got to witness my first ever tern colony live in action. This is where I learned the real tricks of the trade! Having never stepped foot on a seabird colony I didn’t really know what to expect…  My first morning on the reserve came in the aftermath of an invasion, by no less than two undetected hedgehogs, which had been stealthily scoffing eggs, over the course of the previous week.” 

“As I woke every morning at 5:30 a.m. to begin my shift, I’d love to say I was bright eyed and bushy tailed. Sadly this wasn’t the case! Grabbing my cup of tea, binoculars, telescope and paperwork for the day I scrambled out to the hide, falling over fences in the process. This was definitely the most stressful part of the day. Nevertheless, once settled in the hide, all was forgotten as I spent the next 8 hours admiring the scenery and observing the behaviour of the terns diving into the sea catching fish and incubating their nests.”  

A pair of two day old chicks (photo Eilis Hogan)

“The first eggs began to hatch on the 9th of June. Another volunteer Brian and I couldn’t get over how cute and fluffy they were and we were so excited to discover them. I still get excited every time I see one! Once the chicks were one day old, Chris, Steve, Brian and I began to ring them collecting data on their weight and wing length while doing so.” 

“These birds are very hardy given their little size, with all the odds against them. With challenges from predation and high tides washing up their nests, they never seemed to give up!”.

In the event of a nest loss most pairs will attempt to relay in a different location. As my volunteering experience was coming to an end, a second round of relays have started to hatch and there are many more chicks to come as the birds continued to lay up until the 25th June. Fingers crossed no more predators or high tides will get at the Little Terns this season!”

“My overall experience working on the little tern colony in Kilcoole has been amazing. I have learned so much about little terns and what it takes to protect them and other birds within this very special mix of wildlife habitats along the seashore in Kilcoole. It has definitely encouraged me to continue working with sea birds in my future career!”

Not quite flying, a hatchling hiding behind seaweed.

From all of the Wardens and other volunteers on the project, we would like to thank Eilis for her hard work and great commitment. At the time of writing, there have been 20 successful nests where the chicks have already left and will soon fledge, there are currently 79 active nests and 126 chicks have been ringed to date. The first fledgling was witnessed taking to the wing on the 28th June. All in all, after such a difficult start, there is a feeling amongst the camp that this may well be a successful year again, for the Little Terns at Kilcoole. 

Bye for now,

Darren.

Hungry beaks to feed. Little Tern returning with Sandeel. (Credit Darren Ellis)