Spring migration is an exciting time of year for birding in Ireland.
During this relatively brief window from early April until the end of May birds are on the move. There’s a changing of the guard as our winter visitors, like waders, ducks, winter thrushes and the occasional exotic visitor like the bohemian waxwing, depart for their breeding grounds further north, and we see an influx of birds from the south moving into Ireland.
Some of the more familiar migrants are returning here to breed: birds like swallows, sand martins, house martins, willow warblers, spotted flycatchers, sedge warblers and cuckoos, for instance. Other long distance migrants, like the impressive osprey, don’t currently breed in Ireland, they simply pass through on their way further north — offering a brief opportunity for Irish birders to catch up with them at this time of year if their luck is in.
And then there are the vagrants… birds that shouldn’t really be here at all. They arrive by mistake — overshooting their intended mark through bad luck or unfortunate circumstance, and ending up in places you’d never expect to find them. These are the rarities, often from distant parts of Asia or North America, that can prompt keen birders to travel the length and breadth of the country to add a tick to their Irish list.
One of the most appealing aspects of wildlife watching in general, and birding in particular, is that you literally never know what you might encounter when you venture out. During spring migration (and again in autumn… but we’ll cover that in more detail later in the year) that sense of anticipation… of never quite knowing what you might see… is heightened exponentially.
What is Spring Migration?
Lots of animals migrate… including land mammals, bats, insects, moths and butterflies… but when we talk about spring and autumn migration we tend to think primarily about the most mobile of our fauna: birds. More specifically we’re talking about the movement of birds from one place, where they have overwintered, to another where they breed and raise their young and vice versa.
Why do birds migrate
In a word: food. Or more accurately, access to the right kind of food, at the right time of year, to allow them to rear the maximum number of young possible.
Insect eaters like the spotted flycatcher, the barn swallow and many warbler species can’t survive the winter in Ireland because their principal food source, flying insects, disappear during the colder months (how many swarms of flies and midges have you seen in Ireland in January?). So they head south, to balmier climes where they still have access to this essential food source.
That begs the question why do they bother making the return journey? Why not stay in these milder climates all year round?
It’s to do with food again. During the summer months there’s a massive seasonal spike in the availability of flying insects at northern latitudes. Insects have to cram their life-cycles into a finite weather window between spring and autumn, so everything happens at once. This glut of winged protein coincides with longer day lengths the further north birds fly… giving birds more time each day to forage. It’s an ideal combination for successfully rearing young birds.
Even birds that eat seeds and fruit come to rely on this abundance of insects — with most small birds choosing to feed nestlings on protein rich invertebrates rather than the less digestible food the adults eat themselves.
When does Spring Migration happen?
The short and obvious answer is of course “in spring”!
Typically the window for spring migration in Ireland spans the last few weeks in April into the first few weeks of May, although it can shift a little either way, and be longer or shorter depending on the prevailing weather conditions — particularly wind. Many birds — especially smaller species — rely on a helping hand from favourable winds to make some truly astonishing journeys.
You can use cues from your surroundings to give you a heads up on when to start watching for migrants.
- Watch your resident birds: when your local birds start to sing, pair up, gather nesting material and generally gear up for the impending breeding season, you know the arrival of spring migrants is just around the corner.
- Keep an eye on buds and blooms: trees budding and the appearance of the first blossoms and blooms are another good sign that spring is well under way, and that migrants will soon arrive.
- Listen to the buzz: when you notice bees buzzing around parks and garden, and see small clouds of hatching flies hanging in the evening air, it’s a sure sign that the migrants that feed on them will start arriving before too long.
- Look out for early arrivals: learn which migrants arrive first in your area every year… and look and listen out for them from early April onwards. Once they arrive, you’ll know that other migrants won’t be far behind.
The best places to look for spring migrants in Ireland
While migrants can turn up just about anywhere in Ireland, offshore islands and coastal headlands tend to be the best spots for finding a concentration of incoming birds. Anywhere that juts out into the sea with a few shrubs or small trees to offer cover to tired migrants is fair game. These promontories tend to be the first bit of land migrating birds see as they cross large expanse of water, and they instinctively make a beeline for them.
There is nothing to stop migrant birds from flying on, and turning up further inland. Indeed many of our summer breeders will move inland to find the right breeding habitat, and in time will be seen and heard across the country. However, dispersal across a much wider area tends to mean that migrants can be difficult to pin down away from the coast. As a birder you greatly increase your chances of hooking up with migrants if you put yourself in locations where the birds are likely to concentrate on arrival.
The south and east coasts
Most migrants arriving in Ireland in spring will hit coastal locations in the south and east of the country first. Areas like the Old Head of Kinsale, Mizen Head and Cape Clear Island in Co. Cork are acknowledged migration hotspots, although any southern island or headland can harbour a significant fall of migrant birds when conditions are right. East coast locations in County Waterford and Wexford can also attract significant numbers of spring migrants as they arrive from the continent.
The west coast
Although further from the “normal” migration routes (birds arriving into Ireland from Europe, Africa and occasionally vagrants from Asia), the headlands and offshore islands of Ireland’s west coast still attract their fair share of spring migrants. They are also ideally situated as the first point of landfall for American birds blown off course by Atlantic storms.
While American vagrants tend to be more of an Autumn phenomenon, a they occasionally turn up, a long way from home, on Ireland’s west and south west coasts in spring.
The ideal weather
Balmy spring days (not that we get too many of those in Ireland, mind you) might be lovely for a stroll on the coast… but they are not necessarily the best conditions if your goal is to find often elusive spring migrants. Check the forecast before planning your trip. If you arrive in the right spot just after a spell windy weather you could maximise your chances of seeing more birds.
Ideally you want a spell of sustained wind blowing from the direction the birds are coming from — so from the south and east for most spring migrants — although on the west coast sustained westerlies blowing in from the Atlantic can carry a few American surprises with them.
In good weather birds that arrive on the coast tend to move on fairly quickly in search of more favourable habitat. In less agreeable conditions — such as when it’s raining heavily, birds tend to take shelter and wait for the inclement weather to pass.
I’m not suggesting traipsing around a headland or offshore island during spring downpours… but often the best time to search for migrants is just after a spell of bad weather. Birds that have taken refuge from the poor weather conditions tend to be more active, busy making up for lost time, foraging and refuelling for their onward journey — and all that activity makes them easier to see.
Spring Migration: The Usual Suspects
Here are just a small selection of the many migrating birds to look out for as they start to arrive in Ireland each spring (dates are rough guidelines and can and will shift from year to year… it’s also worth bearing in mind that a few individuals of any species will often arrive much earlier).
Bear in mind this is a small sample, and that literally anything that moves a significant distance in spring, however unlikely, could conceivably turn up in Ireland — so keep an open mind.
March: wheatear, chiffchaff (the “earlies”)
April: blackcap, sandwich tern, common tern, Arctic tern, manx shearwater, willow warbler, swallow, sand martin, house martin, sedge warbler, grasshopper warbler, wood warbler, cuckoo, whitethroat.
May: swift, spotted flycatcher, pied flycatcher, garden warbler… more of the above… and who knows what else!
Spring Migration: what you’ll need
There’s very little you’ll need other than your eyes, ears, patience and enthusiasm to look for spring migrants — but here are a few things you might want to take with you to make your outing more productive.
- Good Binoculars: binoculars are perhaps the number one birding accessory, and few birders would be without a good pair of binoculars when they’re out in the field. They help you spot elusive migrant birds at greater distance, and reveal plumage and behaviour that can help with the identification of potentially unfamiliar visitors. It’s worth investing in good binoculars; a decent pair will not only enhance your views of wildlife every time you venture out, but will also last for many years. You’ll find independent reviews of a selection of high quality birding and wildlife binoculars in our gear review section, and check out binoculars we’ve tested and recommended here.
- A notebook and pencil or digital voice recorder: one or the other is important for noting the details of unfamiliar birds so you can check their identification later in a field guide. A notebook has the advantage of allowing you to sketch key characteristics for reference later. The later can be handy for recording bird songs and calls… again to help with later identification.
- A good field guide: a high quality field guide is essential to help you identify unfamiliar birds. Remember that during migration you may well encounter birds that don’t usually occur in Ireland, so you may need a guide whose scope extends beyond Ireland’s birds. The Collin’s Bird Guide is the “Birding Bible” for Europe, and a book I heartily recommend. It covers all of the species you’re likely to encounter in Europe… including rare vagrants — so, in theory at least, with this in your glove box you’re all set for whatever spring migration can throw at you.
- Reliable outdoor gear: spring in Ireland means unpredictable weather — so you need to dress accordingly. Warm layers and a good waterproof outer shell are the key to comfortable spring birding in Ireland. You’ll find a selection of outdoor clothing reviews in our gear review section.
The Optional Extras
- A superzoom digital camera: or a dSLR with a long lens. It can be handy to get a record shot, even a distant one, of an unfamiliar bird to aid identification later. A photo also helps avoid confusion if you find something really unusual that nobody else is around to verify.
- A spotting scope: cumbersome to carry around a headland with you, but a spotting scope and tripod can be invaluable for scanning distant hedgerows for migrant activity, and is essential if you’re scanning the sea for migrating seabirds. You’ll find reviews of wildlife and birding spotting scopes in our Gear Reviews section.
- A “where to watch” book: a book detailing the best sites around Ireland can be invaluable if you’re venturing outside your local area in search of migrants. The excellent “Finding Birds in Ireland” by Eric Dempsey would be top of my list, with “Where to watch birds in Ireland” by Paul Milne and Clive Hutchinson coming in second.
- Smartphone apps: electronic field guides for your iOS or Android smartphone can provide quick and convenient access to check features, songs and calls of birds you see. I highly recommend the Collins Bird Guide app for Android and iOS devices (search for it on the app store). Another potentially useful app is Cornell Lab’s Merlin Bird ID, which attempts to identify birds based on your location, time of year, and your answers to a series of questions. It can even attempt an ID from a photo
- Online news: following the various bird news services (@KerryBirdNews, @ECoastBirdNews, @WexfordBirdNews, etc.) on twitter can help give you up to the minute news of what’s arriving where. The website Irish Birding is also a great resource for bird news from around the country, and you’ll find various groups if you search on Facebook.
Get out there… and don’t forget to share!
By far the most important resource for finding spring migrants is time… time spent out in the field actually looking for them.
It’s funny, but the more time you spend looking the “luckier” you’ll tend to get. So get out there and find some migrants… and don’t forget to share what you discover with us in the comments below, on the Ireland’s Wildlife page on Facebook or with @WildIreland on twitter.