Saturday, October 9, 2010

Full Circle

September 1st finally arrived; the day I came full circle and completed my first full year working at Cape May. And what a year it's been! Record snowfalls, a hideously wet spring, then the summer drought with temperatures reaching 100F - quite a variety of experiences for sure. So now September has come and gone again and, with it being the peak period for bird migration, it's been pretty much impossible to find time to write a blog - especially as I was trying to keep a diary going! So, I'll cobble together some highlights of the season over the next few posts to give an idea of the wonders of a Cape May autumn (and there's still plenty to come yet!).

After the amazing Monarch departure, it went a little quiet for these amazing long-distance travellers for a while; but small numbers still continued to pass through and their black-and-orange colours always look good when they are feeding at the Giant Sunflowers in the Cape May Point State Park.

One useful thing to know about Monarchs though and that is that not everything you think is a Monarch, is a Monarch! So here's a classic Monarch from below, feeding at Japanese Honeysuckle - but compare it with the next picture...

...still looks like a Monarch - or does it? This in fact is a butterfly called a Viceroy which isn't even in the same family as a Monarch (it's actually related to the fritillaries and admirals) and yet looks pretty similar. Similar enough, in fact, that once a predator has learned that Monarchs are poisonous and should be left alone, they leave Viceroys alone too. Initially this was thought to be one of the most basic forms of mimicry, called Batesian Mimicry, where a harmless species looks like a poisonous one and thus benefits from this arrangement by not being eaten. In fact, it turns out that Viceroys are poisonous too - so called Mullerian Mimicry - where harmful animals with similar traits look similar, that way the message gets across quickly and they're all left alone; sort of benefits both sides really! To most predators, the two butterfly species above look similar enough that they are considered to be the same thing. With our more discerning eye, we see many differences, the most obvious being the extra black line across the middle of the Viceroy's wing. There are other subtle differences too, in the arrangement and shape of the white marks for example.

From above, the same differences as can be seen from below are evident, with the line across the hindwing on this Viceroy being the most obvious feature.

Monarch top side - compare with above. You can also tell male and female Monarchs apart from each other. This is a male, as told by the narrow black veining and the two round, black dots on the hindwings.

Butterfly migration hasn't been all about Monarchs this year, however. Common Buckeyes have been staggeringly abundant - even as I write in early October there is 100 or more in our meadow, feeding avidly at the Frost Aster flowers. I took a photo of this one as it paused on a fence post and posed nicely for me along Yale Avenue.

With all the Monarchs around, eyes were on the butterfly world and, with the added attention, several less common species were found. I found this Pipevine Swallowtail in the state park on September 13th and managed just one quick shot before it sped off across Lighthouse Pond. This is only the second time I've seen this species, and the first time I've managed to get a photo!

Our own butterfly garden is still at very humble beginnings, but the mass of plants we've been given by friends and neighbours has certainly got us off to a good start. In this bed, a Mexican Sunflower stands tall above New England Aster and Red Sage.

And here's some of the competition trying to attract butterflies too! The show of wild Giant Sunflower at the state park has been spectacular this year, especially when they were adorned with Monarchs!

Another insect mimic that isn't quite what it seems! This may look like a bumble bee, but notice the long antennae. This is a Snowberry Clearwing - a species of hawkmoth - which is able to fly by day unmolested as it looks like a bee, so is left alone. Unfortunately this is yet another of those New World things that has been wrongly named and now it's too late to change; the clearwings are actually a completely different family of moths, unrelated to the hawkmoths. This should best be called Snowberry Beehawk as it is closely related to the Beehawk moths of the Old World. This is a common species around Cape May and best told by its black legs (though the light shining on them makes them look pale in places here). The similar Hummingbird Clearwing has white legs.

Still on things in our garden, our local Black Rat Snake turned up again recently, hanging out for a few days in one of our Norway Maples. With the migration of tree-loving warblers now under way, it made me wonder whether his ploy of hanging out in the trees was to have a go at catching small birds for lunch.

Something that struck me this month was how small birds have a habit of always managing to get something between you and them when they flit through the trees and seemingly pick a spot to land at random. How do they do that? Are they that good at calculating sight lines that they can pick a spot on a branch, knowing that they'll be at least half hidden from view behind a leaf or twig? So it seems, as it just happens so often. Now, having covered that, I have an excuse for some dodgy pictures of birds half hidden by other objects! Here's a Veery, one of the small Catharus thrushes and a master at the art. This one was in the small Sassafras tree that is just a couple of feet from my office window - good job the camera was handy!

Another sneeky peeper, this Philadelphia Vireo came in nice and close but - typically - never quite gave itself up to the camera lens and always managed to keep a leaf or twig between us. It's been a particularly good autumn for this species which is regular but never common at Cape May.

Again, a perfectly positioned bird! This Great Crested Flycatcher was in a mixed flock which came in close when I was luring them in with a bit of 'pishing' but it still strapped a piece of juniper to its face!

But just to show that it can be done, here's a Carolina Chickadee - a species that seems to like us so makes a bit more of an effort to pose nicely! This bird was in the same flock as the flycatcher above but came to within a couple of feet of me, which meant I had to back off to get it in focus!

Now here's a bird that set me thinking about how field guides are written. Shouldn't we have illustrations that show the birds as you would see them in the field? Well, here's a typical view of a Northern Waterthrush - if only I could have a pound - or a dollar - for every one I've seen like this!!

Eastern Kingbirds start to move south relatively early and numbers at Cape May peak in late August. Higbee's Beach is a great place to see this species then, when up to 300 can be gathered in the Sassafras trees were they feed avidly on the ripening fruits. As most birds will have finished breeding by this time, I was surprised to find this young Eastern Kingbird which had clearly not long left the nest, judging by its stumpy wings and tail. Surprising because of the date as it was September 7th when I chanced upon this little chap near Rio Grande.

With the tourist season not quite over and guests staying with us, we took the opportunity to hire some kayaks and see the harbour and backbays of Cape May from a different angle. One of my favourite shots from the day out was of this Forster's Tern which really didn't seem bothered by us in our kayaks - I guess it could clearly tell from the way we were floundering around that we weren't a threat to it! I actually took this picture with a little point-and-shoot Pentax I have, but which is ideal for kayaking as it's waterproof!

I haven't said much about life on the beaches of late, though to be honest most beaches are best avoided during the summer! So, here's a few pictures from the sandy strands of Cape May Point. This Lesser Black-backed Gull was one of the first of a good run of this species this autumn and turned up on September 2nd, being one of four present that day. Although a European species, Lesser Black-backs are expected here each autumn and it seems likely either that a small breeding population has become established - perhaps in Greenland - or that birds have established a regular migration route which takes them to wintering grounds in the Caribbean and Florida.
A flight shot of the same Lesser Black-backed Gull reveals how messy they can look when in full moult during late summer. This is clearly a third calendar year bird, moulting into its adult-type grey wing feathers for the first time. Notice how the flight feather moult starts with the innermost primaries and works sequencially outwards. It has re-grown the first three completely, the fourth is almost fully re-grown and the fifth (with a neat black and white tip) is getting there too.

While on the subject of gulls, I dropped in this shot of a worried-looking Ring-billed Gull. There was a very real threat of Hurrican Earl making landfall somewhere close to Cape May at one point and all the emergency services were on stand-by. During the height of it all on September 2nd I took a stroll along a breezy but wonderfully empty beach and found this guy digging in behind a wall of strandline debris just in case!! And that was it - Hurricane Earl, a damp squib in my book, and not even damp actually!

Despite Hurricane Earl fizzling out to nothing locally, a lot of seabirds were pushed onto Cape May's beaches to ride out the worst of the weather. After a number of near misses which were starting to get a tad annoying, I finally bumped into a Sandwich Tern off Coral Avenue, courtesy of Michael O'Brien. Of course, after that, the inevitable happened and I then ran into one or two more over the following few days. This ringed adult was on the beach near 2nd Avenue Jetty. This is an uncommon species in Cape May with just one or two wanderers reaching here in late summer each year from breeding grounds much further south.

While enjoying skimmers and terns on the beaches on September 9th, I was intrigued by the bird on the left. These are clearly both Royal Terns, a common species at Cape May, though not a regular breeder with us at present. What intrigued me about the bird on the left is just how relatively dainty it looks when compared with the typical bird on the right. While Royals Terns do vary a little in size, bill size is one of the features that is used to define the West African population from the Western Atlantic population in the USA. This smaller-billed bird would certainly not look out of place in The Gambia where I have seen many birds of the race albidorsalis and it does make me wonder whether some of them make it across the Atlantic on the back of stormy weather. Something to ponder upon over a few beers I think!

The wide expanses of intertidal flats and beaches around Stone Harbour are great places for shorebirds and a few Red Knot were on their amazing southbound migration from the High Arctic to South America and had dropped in for a refuel last time I was there. This is clearly an adult with remnants of its rufous breeding plumage still showing. Note the old and very worn wing coverts with their very pointy tips, the result of the softer parts of the feathers wearing away and just leaving the central shafts.

In contrast to the adult above, here's a far more dapper looking juvenile Red Knot with its neat chevrons along the flanks and tidy rows of round-tipped wing coverts. Such differences in wear between adults and juveniles at this time of year can be a useful way to age birds where plumage markings are much more similar between different-aged birds than they are in Red Knot.

Another long-distance migrant that is quite common at Cape May during August and September is Pectoral Sandpiper - here a very neat juvenile (look at those smart wing coverts!). These birds go well south into South America and have the long wings typical of such long-haul travellers.

One of the star turns of this year's autumn migration here and an uncommon species in Cape May - at least south of the canal - was this moulting adult Hudsonian Godwit. Yet another long-distance migrant, this bird spent time hanging out at Bunker Pond and couldn't have been more obliging. The bill seems to be particularly long on this individual which suggests that it is probably a female.

A bird that is easily missed here is Sora Rail, as they so often prefer to keep themselves tucked away in marshside vegetation - though they're pretty easy to hear! This one bucked the trend and spent the best part of a week feeding right out in the open on Lighthouse Pond during late September.

Well Cape May is, after all, all about migration and September is the peak month for the movement of American Kestrels - though October is continuing to be good for them this year too. On October 20th, Megan and I went down to Sunset Boulevard in the evening where up to 40 American Kestrels had been gathering to feed on grasshoppers in the open, short grassland there. It was getting late by the time we got down there, but here's just a few of a party of seventeen which were strung out on wires near the Magnasite Plant and put on a fabulous display. With Merlins zipping through every few minutes too, it really was a treat!

As if we needed signs from the birds that October was only just around the corner, a nice Blue Jay movement took place on September 29th and my Wednesday walk started with a wonderful flock of 147 of them flying around the lighthouse and seeming a bit unsure what to do next. Blue Jays are poorly equipped for taking the Delware Bay on so many probably head back up the shore to cross further north where the bay is much narrower. That morning, we had at least 300 Blue Jays looping around Cape May Point with some bigger flocks coming a few days later.

Another sign of late fall - come late September, come the kinglets. This Ruby-crowned Kinglet was part of the vanguard of what is proving to be a very good autumn for this species.