November 27th – Winter’s Onset

The beach at Castalia Marsh at low tide. -DOL


Grand Manan Island, which sits at the mouth of the Bay of Fundy, is a great place to see birds – one of the major factors that attracted Marg and I to it in the first place. We bought a small cabin there with an extensive boreal forest bush and seek our repose whenever we can afford the time. I finished a 32-day stint on the CCGS Hudson on the 7th of November and we high-tailed it to the cabin for a couple of weeks before heading into the “holiday” season.

You never know what you’re going to see on the island or where you might see it – there’s many good spots – but avian oddities could show up anywhere. A couple of Summers ago I found a Lark Sparrow and a Lark Bunting (2 western species) feeding together not more than 400 meters from the cabin, just along the coast. But the bottom line for birding is that if you don’t go and look you won’t see anything and, as any birder can tell you, this becomes an obsession….

A good place to look on Grand Manan is Castalia Marsh. A couple of Summers ago a Burrowing Owl spent over a month along the protective rocky breakwater there and just this past August there was a Snowy Egret and a Little Blue Heron foraging in the marsh. On the 11th though I went there in search of a particular bird – Snow Bunting. For me, this is a sure sign that Winter is on its way – the harbinger of snow and cold….the stuff that makes you a Canadian.

As you can see from the picture above, Castalia’s shoreline is an excellent spot for Snow Buntings. I was wasn’t disappointed – a flock of ~24 flew up, swirled around like shorebirds (which I equate them with) before resettling and scurrying around in search of food. As you scan the photo from right to left you’ll see why this is such a good spot for them: rocky seabed exposed twice a day – the buntings forage out amongst the rocks looking for zooplankton; then comes lines of brown algae, mounded by recent storms – another good source of food, especially small insects; then a cobble beach where the birds can find grit to help them digest and where they “disappear” when they sit down to rest; and last, a sand dune covered with grasses that, at this time of year, are festooned with seed heads and which provide not only food but cover for the birds and protection from the winds. They were pretty skittish and took off when I got within 150 meters, giving their unique alarm call. But after a couple of circlings they dropped again into the exposed rocks and continued foraging. As I slowly approached they scurried up the beach and into the tall grass and disappeared. I left them to their feeding. The flock remained for 11 days at least. On the 22nd, our last day on the island, I could only find 1 lone bird. The flock was nowhere to be seen, at least not in its usual locale. They may have taken off for the mainland or merely shifted to another area further along the beach. But one thing was clear: Winter must be on its way!
Rick

Bad Luck

As I’ve tried to point out in the last couple of postings, migration is a difficult time for birds. Mortality is high especially with estimates as high as 80% of young (Hatch Year) songbirds don’t survive their first year. I just finished a paper whose authors studied populations of Black-throated Blue Warblers both on their breeding grounds and in their wintering grounds. As the birds stay in place once they reach these areas they are referred to as their “stationary periods”. The authors noted that “apparent mortality rates were at least [italics mine] 15 times higher during migration compared to that in stationary periods and more than 85% of apparent mortality in [Black-throated Blue Warblers] occurred during migration.” And similar findings could be made for most songbirds.

Still, every Spring colourful migrants show up speeding their way to nesting grounds. So some are successful. For these birds everything fell into place: good nutrition at the right times; predator avoidance; sustaining and restorative resting/feeding areas on route; good weather and helpful winds; a patch of desired habitat when they made it home.

Sometimes birds do the right thing, elements are falling into place and they should be successful but meet with…how else can I describe it…simply, bad luck.

I have been aboard the CCGS Hudson for the past month doing AZMP surveys in the lower St. Lawrence River and Gulf of St. Lawrence. [AZMP stands for Atlantic Zone Monitoring Program and consists of comprehensive oceanographic surveys in the Canadian Atlantic.] We were just finishing our area – the Quebec Zone (there are a number of zones in Canadian waters) – and were about to enter the bay surrounding Sydney, Nova Scotia when we “got the call”: there was a vessel in distress about 250 nautical miles (NM) out in the open Atlantic SE of Newfoundland.

The Hudson wears two hats: it’s a research platform for Oceanography (Beford Institute of Oceanography, Department of Fisheries and Oceans, and several others) and it’s a coast guard vessel with SAR (Search and Rescue) responsibilities. SAR takes precedence over research. As soon as we got the call the vessel made a hard turn to port and we were headed offshore steaming at 14 knots, pounding into 4-6 meter waves. [I still did my counting but it’s awfully hard to see birds through salt spray pelting the windows.] Just after midnight we came up with the ship – Fishin Fionnatic (pronounced Fanatic) – a small (15 m.) fishing boat that had been hit by a “rogue” wave and had its port side windows stove in. The crew had been able to clear the lower decks of water and it was able to putt along under its own steam at a steady 7 knots. Even so, we escorted it all the way into Canso. That was bad luck. But the boat wasn’t migrating….

However, when we were still 73 nautical miles east of Canso I watched a BALTIMORE ORIOLE fly onto the ship from over open water. It stayed on the vessel, hunkered down under some machinery, obviously resting, head back under its wing. Shortly before it got dark, when we were still 23 NM from shore, I saw it fly toward the back of the ship but never saw it again after that. I didn’t find it on the deck the next morning. So it likely flew away from the ship…whether it was successful reaching shore I can’t say. But, to me, this was a case of a migrant (orioles winter in Central America) running into some bad luck. There had been a big storm, a low pressure system with counter-clockwise winds, on the eastern seaboard of the U.S. I’m guessing (but am pretty sure) that this bird got caught up in the storm as it was flying south and was sucked up and blown well to the north before it found our “island”. Just another of the trials that migrating birds must endure. And with the climate changing as it is, birds will be experiencing more of them.

Balitmore Oriole, lost at sea

Baltimore Oriole, lost at sea

Musings on a Blackpoll Warbler

The big blow, which started during the night of October 17th, was over; the violent SE winds, which at one point hit 60 knots, had subsided to 10-13 knots; and the 4-5 metre swell was flattening out. We were headed N in a big open stretch of the Gulf of St. Lawrence – if you put a dot in the middle of the ocean bordered by the east end of Anticosti Island, the west coast of Newfoundland and the north shore of Quebec….there we’d be. Out of the corner of my eye I noticed an UNPA (Unidentified Passerine) fly to the ship from the west and circle around to the back of it. When I took a break from the bridge I went to see if I could find it. Maybe it had taken a look and kept going….

I came upon it on the stern deck hopping around looking for something to eat amidst a number of heavy wire mesh bins holding equipment – a Blackpoll Warbler. Sadly, insects were few and far between after the big blow. Undaunted it kept searching. I returned to the bridge and never saw it again. Maybe it succumbed to starvation and hypothermia hidden away in the ships’ gear; maybe, finding no food, it kept going; and if it did, maybe it made it to land….or maybe it didn’t.

I’m not sure what paper(s) I got this from but I’ve read that around 80% of small songbirds don’t make it to their first birthday. 80%! I used to think that was terribly high. But, when you give it some thought, maybe it’s a miracle that it’s not higher. Take this little warbler. Let’s assume that it was a young one, hatched this past Summer in the boreal forest 200 km to the north (could have been more, could have been less). First of all, it would have to survive 12 or so days as an egg without a predator noticing its parents building a nest and then sitting on the eggs. Then it would have to survive another 12 or so days as a nestling, rapidly growing feathers to the point it could effectively thermoregulate and based on its parents ability to find the food necessary for this growth and deliver it furtively enough that the nest wasn’t detected. And then, upon leaving the nest, it would spend a week or so moving with the parents, being fed but also learning how to forage until the parents cut them loose to pursue their own destiny – complete moult of all feathers and then migration. At this point the young bird would also moult – but not completely, mostly body feathers and some wing coverts. And it would begin to move around the natal area (and beyond) – “disperse” – familiarizing itself with the area so that it would recognize “home” and identify some future possible nesting sites when it returned. And it would have to do all this while feeding itself and recognizing and avoiding predators. (At the dispersal stage, young birds are often clumsy fliers and an easy target for avian predators.)

So….lots of early hurdles but let’s assume that the bird makes it. Now the big challenge begins: it gets the urge for going, to make that epic flight from the boreal forest to the southern Maritimes/New England and then, flying NONSTOP across the Atlantic to South America. For this particular bird the first significant hurdle would be the crossing of the Gulf of St. Lawrence. For this bird to be where it was when I came upon it a number of explanations might be proferred: it started it’s crossing from the N shore the previous might, before the storm, and got blown backwards; it was making the crossing across Cabot Strait (between Newfoundland and Cape Breton) and got blown back to the NW. In both of these scenarios the bird found itself out over open water, running out of fuel, and the ship was an “island” that it sought refuge on. Another alternative was that it headed out when the storm started to abate – so a late morning take-off – landed on the ship for some respite and then took off again. This last option is a bit of a stretch if you consider that most songbirds fly at night. But it was getting late in the year and maybe the urge to go overcame the need to fly at night. Remember, I had seen a variety of songbirds a few days before heading across Chaleur Bay and I’ve seen warbler diurnal migration across the St. Lawrence in May at Tadoussac – diurnal migration in songbirds may be more common than we think.

Just for the heck of it, let’s imagine that this particular Blackpoll took off after a brief respite on the ship and carried on to the N shore of Nova Scotia. At this point it would have to find places to shelter and, especially, to feed, to recoup the significant energy it took to make the crossing in adverse conditions and to prepare for the flights to come. It would also have to be on the look-out for predators – accipiters move with migrating songbirds to take advantage of this flying buffet heading south.

Now the bird would have to make its way S to a place it could fatten quickly possibly changing the majority of its diet to berries (dogwood berries are particularly attractive as they have a relatively high lipid content). This would entail flights totalling several hundred more kilometers to get to the “jumping off place”. Here, after putting on a lot of fat, in many cases doubling its weight in about 2 weeks, the bird is ready and waiting for the “right” weather system, one that will provide assistance to lift its considerable bulk off the ground and push it SE until it meets up with the NE trade winds which will blow it over to South America – if the trade winds stopped for some reason the birds would simply keep flying SE until they ran out of fuel somewhere far out over the ocean.

I doubt very much that birds “feel” joy but after 80+ hours in the air over a hostile watery environment you might infer a feeling of, at least, relief…..It’s been a struggle but the bird has made it to its Winter home where it will have to find its way: identify food sources and recuperate, avoid predators, and simply get by until the urge for going in the Spring starts up.
Now, think of all those steps. There are so many things that could go wrong and impact the journey: predators along some parts of the route; contrary winds/weather systems – more so now with climate change variables; a poor growing season resulting in a lack of food for fattening; urban/suburban development limiting feeding and sheltering areas in the north; habitat loss limiting available territories in the wintering areas. And this is just half of the yearly cycle for this species.

Is it any wonder that 80% don’t make it back?

October 22, 2021 – UNPAs

Over the past nine years I’ve spent over a year at sea, counting seabirds in the Atlantic and Arctic Oceans from the bridge of large Canadian Coast Guard vessels. There is a clearly defined protocol that is followed: I focus on the birds on one side of the ship (usually the port side) and try to place them in terms of distance from the ship within a moving 300 square meter area. The area is moving because….the ship is. Ideally each bird (or birds) is identified; counted; sorted as to whether it is sitting on the water or flying; and then placed in a distance category relative to the ship: 0-50 m, 50-100 m, 100-200m, 200-300 m, and >300 m. Birds on the opposite side of the vessel may be noted and recorded but they don’t figure into the calculation of bird density; i.e., number of birds per square kilometer which this methodology strives to achieve. Birds are counted in 5-minute “batches” or “watches” which are continuously renewed as the count progresses.

The recording of each record is done using Dragon – voice recognition software – which populates a database as you speak. To make things easier, instead of writing out the long form of a bird’s name, only the 4-letter alpha code is entered. Those familiar with banding will recognize this right away as we use the same method for recording the birds we band. Disregarding exceptions (and there are many!), it works like this: you take the first 2 letters of the first name and the first 2 letters of the second name and, presto!, you have the alpha code. So….let’s practice: Song Sparrow? SOng SParrow = SOSP. Northern Gannet? NOrthern GAnnet = NOGA. Simple right? In most instances this works but you have to learn the outliers separately: e.g., Black-throated Green Warbler is BTNW so you don’t confuse it with Black-throated Gray Warbler, which, of course, is BTYW. Simple…right?

So let me get back to the gist of this post. Usually I don’t see many landbirds when I’m out on the ocean unless I’m travelling during migration periods (my last two blogs were about this). Now, when a landbird goes by you don’t have a lot of time to make a discrimination; the bird is moving at speed and the ship is moving at speed (as well as up and down and sideways at times) and if they’re moving in opposite directions then they’re moving at great speed. Further, you can’t wait for the bird to land in a convenient tree or bush so you can sneak up and make an ID. Unless that bird lands on the ship, on the forward deck, you’re going to have a hard time. Because the other reason is that….you’re not really looking for them. Your concentration is on the sea out in front and to the side, usually at quite a distance. And then suddenly this little feathered blob whips into your peripheral vision moving at speed and by the time you can get your binocs positioned and refocused it’s gone. And, although you’d dearly like to make an identification, you hope that it doesn’t land on the ship or, if it does, it doesn’t settle in. Too many never leave it alive – it’s a death trap the longer they stay. There’s little to no food and eventually they simply run out of energy and die of hypothermia.

So how do you account for these travellers in the database? If you can’t make an ID they are recorded simply as UNPAs – Unidentified Passerine. I had a few of these today – and I think they had happy endings! We were steaming from the west end of the Strait of Belle Isle (separating Newfoundland from Quebec/Labrador) to the north side of Anticosti Island across a big empty stretch of the Gulf of St. Lawrence. Suddenly, from the corner of my eye, I notice a little group of 5 songbirds winging their way WSW parallel to the ship, which was headed the same way. Only these birds were moving faster than we were and by the time I got my binocs in position all I got was the tail ends – they were sparrow/myrtle warbler size…..UNPAs as I couldn’t be sure.

So, what about that happy ending? First of all, they did NOT land on the ship. They kept going and I watched them through my binoculars until they disappeared in the distance. But there was a lot of water in front of us at this point: about 100 nautical miles to the east end of Anticosti. A nautical mile is about 1.85 kilometers so they had about 185 kilometers to go. The ship was travelling 13.5 knots or nautical miles per hour. The birds easily passed us so let’s say they were going at least 18 knots. Using the conversion above, that works out to 33 kilometers per hour. At that rate they should be able to get there in about 5.6 hours, which is pretty comfortable for these birds if they’re carrying energy in the form of fat. But they had something else going for them: shortly after they passed me the wind began to pick up blowing from the ENE directly toward Anticosti Island. Within 2 hours it went from 4 knots to 17 knots (7 kilometers per hour to 33 kilometers per hour). This assisting wind would likely have cut the travel time by about half!

So, unless a jaeger or a peregrine falcon came along, it’s quite conceivable that these UNPAs spent most of the day foraging on Anticosti Island, resting and building up fat for the next leg – the jump to the mainland.

[For possible predators I used jaegers and peregrine falcons as examples because I have seen them take small birds well out at sea. Jaegers I have witnessed catch Snow Buntings on their passage from Greenland to Baffin Island across the Davis Strait and a Peregrine I’ve seen take a phalarope 90 miles off the coast of northern Labrador – and begin plucking it as it flew.]

Rick Ludkin