Autumn on a boat


I've been lucky enough to work offshore on boats in many parts of the world over the past eight years, in that time watching penguins and albatrosses in the Falklands, boobies and frigatebirds in the Caribbean and shearwaters and skuas off Africa. Most of my time offshore has been in the North Sea — admittedly nowhere near as exciting but there have still been some excellent days watching thousands of seabirds and a few migrants landing on the boats, including a few scarcities.

This autumn I was on a slightly larger vessel than most previous trips (145 m long, 48 m wide and approximately 50 m high), for a total of 62 days during the period running from mid-August to mid-November. We were positioned approximately 25 km off the north Norfolk coast for the majority of the time and I was hoping that a few migrants would find their way onto the boat, as I wasn't expecting a huge variety of seabirds or cetaceans to keep me occupied. What turned up in the end was way beyond my expectations — not only in terms of the scarcities, but also the sheer number of common migrants. I have seen a few Pied Flycatchers, Common Redstarts etc on boats over the years but never in the numbers here.

The first week on site was relatively quiet, a Willow Warbler or two on deck, a fly-by Peregrine and Whimbrel being the highlights. On the evening of 14 August the winds switched slightly to the south-east and within hours it produced. Scanning the main deck I could see a 'fall' of at least six Willow Warblers and then a larger warbler flitted behind a container. After a few minutes it hopped out into view and there before me was an Icterine Warbler. It moved slowly to the back of the boat with a few of the Willow Warblers before disappearing. This is one of the fascinating things about birding on a boat; you can tell exactly when there is an arrival of birds during a change in weather, and there is never a doubt that you overlooked them earlier in the day.

A brief break followed but my return to sea on 25th coincided with another small fall of migrants, with Meadow Pipit, alba wagtail, Tree Pipit and Reed Warbler all first thing in the morning. During the day more birds arrived: two Yellow Wagtails and a Wheatear in the early afternoon followed by three Willow Warblers and a Pied Flycatcher in the evening. It was at this point that I realised that this size of this vessel was going to a real factor in becoming a migrant trap. There are many reasons why I think larger boats are more attractive to migrants than smaller boats, most of which would appear to be pretty obvious: more quiet spaces on deck for them to feed and roost, the vast numbers of lights make the vessel easier to find, lights attract lots of insects creating a larder for the passerines and so on. The combination of these reasons seems to result in more birds lingering on board whereas on smaller boats you may get some passerines circling the boat but they rarely pluck up the courage to land. I'd seen more in one day than I normally would in a few weeks on smaller boats.

Yellow Wagtail.

The next few days were quieter with only a few new migrants, although I did add Chiffchaff and Whinchat to the boat list as well as quite a few moths. Then, on the evening of 28 August, it all kicked off. It had been a quiet day with just an elusive Pied Flycatcher and a rather showy Wheatear all to show for walking the decks. As I started another lap of the decks in the evening I noticed a few more birds: a Willow Warbler, a Tree Pipit … and then, as I checked the front deck, a Garden Warbler flew in off and landed right next to me, followed by a Reed Warbler. Birds were arriving! The front deck was alive with passerines: a few Willow Warblers, a Redstart, a second Pied Flycatcher and then a Spotted Fycatcher zipped past me. The front deck was actually quite small in relation to the rest of the vessel but it was always a good area for birds, sheltered, no work, very little disturbance the perfect combination for resting migrants. I went to check the rest of the boat and from one of the upper decks I checked the front deck again and from my vantage point I noticed a new bird — a Red-breasted Flycatcher that had obviously just arrived! I nipped down to the deck and managed to get amazing views of it. What an evening! Interestingly it wasn't a change in wind direction that resulted in the arrival of birds as there was a westerly element to the wind all day but rather a total drop in wind speed with the wind barely reaching 2 mph after 5 pm. Clear skies meant that unfortunately there was a mass clear out overnight and only a Pied Flycatcher was left on board the next morning — though a Cory's Shearwater more than made up for the lack of migrants.

Red-breasted Flycatcher, 28 August.

Over the next few days a small number of common migrants arrived, with the addition of a Sedge Warbler and a juvenile Sparrowhawk preying on the few migrants that were on board. September 7th would prove to be another epic day on the boat. I was out on deck at first light, the winds had switched from the west to south-east overnight and instantly I could see there had been another fall of birds. Chiffchaffs and Willow Warblers, along with five Meadow Pipits and a couple Wheatears, were the most common birds on board. Added to these were a Redstart, Yellow Wagtail, Pied Flycatcher and a Whitethroat. The best was saved for last, as I was heading down to deck to do some work I flushed a small Acrocephalus warbler. I soon picked it up on deck and got good but brief views of it, a (probable) Blyth's Reed Warbler! Unfortunately I was being called on the radio to assist with some work so grabbed a couple very poor photos and hoped it would be there when I returned later, but it wasn't. Later that day I flushed a Common Snipe off the deck, a Whinchat arrived and three Barn Swallows buzzed around the boat.


Northern Wheatear.

Again there was a lull after the fall and we headed into port for a few days. We returned to the sea on 13 September, by which point the wind had switched to the east again. Again there were a few common migrants on board including Pied and Spotted Flycatcher, Garden Warbler, Song Thrush (2), Wheatear and a Chiffchaff. It was my evening traipse around the decks that again struck gold when I found a Corncrake sitting on a handrail! Truly astonishing and it didn't move an inch right up to the point I went to sleep at 1 am.

Corncrake, 13 September.

Although the Corncrake had moved on the following morning, it had obviously been a precursor for another fall of birds during the night. A total of 34 birds of 15 species were on deck including few new species such as Blackcap (3), Robin, Goldcrest, Grasshopper Warbler and Grey Wagtail. An adult Sparrowhawk and two Kestrels had also taken up residence on the boat and were enjoying the range of food on offer.

The fall continued on 15th and 16th with good number of birds on both days as the easterly winds continued. The 15th started with a Convolvulous Hawkmoth flitting between the lights at 2 am. The table below shows the numbers of birds seen on deck over the two days, the undoubted highlights being a Red-breasted Flycatcher feeding on insects attracted to the lights at 2.30 am on 16th and a Yellow-browed Warbler, my first-ever on a boat!

Yellow-browed Warbler, 16 September.

Over the next couple of days we were hit by a northerly storm. A few migrants lingered but there was no noticeable movement of birds again until 20th. The morning was quiet with a couple Sparrowhawks looking for food, and a few Meadow Pipits trying to hide from them (two unsuccessfully) alongside a couple of Blackcaps, but nothing unusual. An early afternoon tour of the decks revealed how a slight change in winds from north-west to north-east, as well as it dropping to < 5="" mph="" and="" the="" sun="" breaking="" through="" the="" rain="" clouds,="" had="" resulted="" in="" a="" change="" in="" migrants="" on="" board.="" two="" yellow-browed="" warblers="" flitted="" around="" the="" back="" deck="" looking="" for="" food,="" a="" whinchat="" used="" the="" helideck="" as="" a="" perch="" while="" yet="" more="" wheatears,="" redstarts="" and="" tree="" pipits="" arrived.="" this="" movement="" of="" birds="" continued="" into="" the="" 21st="" as="" the="" winds="" slowly="" moved="" from="" the="" north-east="" to="" the="" south-east="" during="" the="" day,="" with="" many="" of="" the="" previous="" day's="" birds="" moving="" on,="" but="" what="" had="" replaced="" them="" was="" an="" unusual="">

The great thing about birding on a boat is that it doesn't have to be a rarity to get you excited and one of the first birds I saw on 21st was a littoralis Rock Pipit, a common sight on the coast but only my second-ever offshore — it was joined by another later in the morning. Mid-morning produced what was probably the most bizarre bird of the month, a Cetti's Warbler skulking on the back deck, occasionally showing well. This was a bird I had never expected to see offshore, due to their limited migration. On a high from these sightings I set off on another round of the deck in the afternoon, only to be called into the bridge to catch a bird that had flown in to it. As I arrived I saw an Acro flitting around the bridge and expected a Reed Warbler as I approached. I was stunned to see a Marsh Warbler sat a few feet from me! After a few minutes of being given the run-around I finally managed to push it out the door and to the safety of the helideck. Having saved the day I finished off checking the rest of the decks and a Reed Bunting had arrived before being flushed by an incoming Hobby. What a day, quality rather than quantity!

Marsh Warbler around the bridge, 21 September.

My final day on board for this shift was on 23rd and again new birds had arrived after a clear-out on 22nd. A dozen Meadow Pipits, four Goldcrests, a Black Redstart and a Yellow-browed Warbler gave the day a real autumnal feel but they were all upstaged again by a common garden bird. Not many people think of Wrens as being migrants so to have two on deck together was incredible. What a month!

Yellow-browed Warbler, 23 September.

I returned to the boat on 30 October wondering what I'd missed over the past month but didn't have long to dwell on that as I woke up to a boat full of birds. There was a noticeable change in species from late September with many classic late autumn birds, mainly Starlings and thrushes. The table below gives a breakdown of the numbers of these for the 12-day period.

Black Redstarts are a bird of early spring and late autumn offshore and they didn't disappoint this autumn, starting with three on 30th. The late autumn feel was finished off with a Woodcock, Blackcap and Chaffinch that day. The month ended in a mixed way, a Mistle Thrush, my first ever offshore the high point, followed by the low of finding a dead Lapland Bunting on deck. A few Bramblings appeared on deck in the afternoon and a Short-eared Owl floated around the boat at dusk.

Black Redstart.

This dead Lapland Bunting only served to highlight the perils of migration.

November started quietly: a Robin was the bird of the day on 1st, another Woodcock arrived on 7th but it wasn't until 8th before things kicked off again. Once again it wasn't a change in wind direction but a drop in wind speed from > 25mph on th to < 5mph="" on="" 8th="" that="" produced="" a="" fall.="" i="" was="" out="" working="" on="" deck="" at="" 2="" am="" and="" the="" sky="" was="" alive="" with="" the="" sound="" of="" thrushes.="" it="" was="" an="" incredible="" cacophony="" of="" sound,="" many="" thousands="" must="" have="" passed="" over="" in="" the="" few="" hours="" i="" was="" out="" there.="" when="" daylight="" sprung,="" there="" were="" still="" a="" fair="" few="" thrushes="" about="" but="" the="" undoubted="" highlight="" was="" a="" flock="" of="" 14="">Waxwings passing over heading south west. A Skylark looked a bit bedraggled on deck most of the day.

Fieldfare and Redwing.

The 9th was a day of really foul weather (foggy, rainy and very windy) — ideal conditions to attract migrants! As I hit the decks at first light it was evident there was a huge fall — birds were flying around everywhere. It was impossible to count them as there was so many, but slowly they started to leave the boat heading for land to the south-west. I positioned myself and started to count them as they left: 4,200+ Blackbirds, 2,400+ Starlings, hundreds of thrushes, Lapwings and so on. It was a truly amazing sight. Woodcocks were arriving all the time, a flock of four landing at the same time and by 10 am there were at least a dozen on the boat. Skylarks, Waxwings, Goldcrests, Siskins and a Crossbill bombed about the decks, rarely settling but adding to the magic of the morning. Birds kept arriving all day and there was a bizarre mix including a few species I'd never seen offshore before: a Coot, a Water Rail and Mealy Redpoll. A late Ring Ouzel finished off a day that produced over 7,000 birds of 26 species!

Starlings huddle together to keep warm on deck.

A flock of thrushes passes the boat.


Mealy Redpoll.

The weather cleared up soon after and with this the birds cleared off — but there was one final surprise on my final day on board on 13th. As I approached the helideck I flushed two bird, which banked away and headed high to the south. Though only flight views, they were unmistakeable as Jackdaws! Yet another common bird that has a whole new meaning offshore — with no noticeably pale collars, where did they come from?

And so came to the end of my time on the boat. Sixty-two days over a three-month period produced 8,564 birds of 65 species and one burning question — what did I miss during October and all those easterlies?

Written by: Ryan Irvine