Naturespeak A naturalist's view of the world

November 5, 2008

Not Your Average Black Bird

Filed under: Uncategorized — wykes @ 9:17 pm

  As a rule blackbirds are not highly rated on the public “good-o-meter.”  Mention a crow or grackle and you’ll get a raised eyebrow at best or a raised shotgun at worse (pointed at the bird in question, not you!). Given their tendency to engage in mob behavior and destructive grain eating binges this attitude is somewhat historically justified. Even among birders, the blackbirds are given short shrift. One simply doesn’t brag about seeing a Starling or a Red-wing Blackbird – they are considered common, vulgar, and borderline evil. You therefore might find it odd that I am bringing up the subject once again. After all, it was only a few short weeks ago that I inflicted the sounds of a Red-wing Blackbird mob upon your ears. 

  My present intention is to direct your attention towards a particular type of blackbird called the Rusty Blackbird. This bird noir is, in many ways, the polar opposite of its brethren. It is a blackbird worth noting and telling others about.

  First of all, Rustys are northern migrants who only put in a brief local appearance during the spring and fall travel seasons (see above). They breed only in the boreal wetlands of Canada from Lake Superior to the northern slopes of Alaska.  And, although they flock together while migrating, these gangs pretty well stick to wetland habitats for feeding and do not make a habit of gleaning farm fields. Even in their overwintering mode, they confine themselves to the wooded wetlands of the lower 48 east of the Mississippi.

  Rusty Blackbirds are well named. The males are basically black with rusty colored feather edges and the females are light rusty-brown all over (see detail here). The gals often have a light brow stripe and some deep reddish patches that give them a distinctive autumn dignity which they lack during the summer nesting season. Both sexes have piercing pale eyes (see here). Those eyes alone will separate them from Red-wing Blackbirds (which have dark eyes). Common Grackles (see here) have light eyes as well, but are easily separated from the Rustys by being larger and having much longer tails. Grackles also exhibit a flashy iridescence that is lacking in their smaller northern cousins.

  Before I introduce you to the call of this unique little B-bird, I’d like to give you one solid reason why you  should look and listen for them. Rusty Blackbirds are becoming rare. Since the mid-1960’s their numbers have declined dramatically. One website author has even gone so far as to claim that the species has ”suffered one of the most staggering population declines of any bird in North America.”  Even though I think that kind of statement should be reserved for Passenger Pigeons, the implications are chilling. The “what” is apparent, but no one is certain as to the “why.”

  Birders and researchers both want to know when and where this blackbird shows up.  Sightings can be reported to the Smithsonian Migratory Bird Center where scientists are attempting to analyze why they are rusting away.

  Perhaps the quickest way to identify this blackbird is to hear its call (Rusty Blackbird Call). Often described as the sound of a rusty hinge, this description doesn’t do the call justice. A hinge creaks only once.  The call of the Common Grackle is more hinge-like. The Rusty Blackbird creaks in an ascending four-parted melody that might be written as “Kritch-A-Loo-Wee.” Birds don’t speak English, which would explain the improper grammar, but the phrase could be roughly translated as “It’ll do we.”  Listen to the individual recording again and then try out this group of Rustys (Gang of Rustys).  Now, compare the sound to a gang of Grackles gracking (Grackle Gang) and you’ll see the difference.

  Lend your eye and ear to landscape before the autumn winds silence these above average blackbirds. We can only hope that silence will remain seasonal.

November 3, 2008

Clam in a Jam

Filed under: Uncategorized — wykes @ 11:38 am

 Life can be tough along the Lake Erie shore. The only consistent feature about this body of water is its inconsistency – in other words, it’s never the same lake two days in a row. One has to be adaptable to meet the daily, or hourly, shifts of mood. Short term water level changes can be the most challenging aspect for the aquatic organisms living in the lake’s near shore waters and coastal marshes.

  Wind tides, or seiches as they are officially known, will drain the water from this western shore within a few hours. Former lake bottom will lay exposed as extensive mud flats for hours or even days. When it is a stiff autumn gale that does the work, the exposure time will be frigid as well. The water eventually returns, of course, but at its own sweet time. If you are a slow gill breathing animal stranded on this chilly mud you can’t afford the luxury of “sweet time.”

  The native mussels that inhabit the mucky shallows can’t swim away with the retreating water like fish and aquatic insect nymphs can.  Even these swift co-habitants are sometimes stranded, so what’s a lowly clam to do? The only thing to do is to dig in with their large muscular foot and clam up.  Individuals like this Paper Shell Mussel (see above) are forced to seal themselves up within a watertight case in order to keep in crucial moisture. This gal (at least I assume it’s a gal based on her feminine proportions) was caught completely off guard and hadn’t the time to dig in before the wind tide struck her piece of Lake Erie bottom a few days ago.

  It was a relatively balmy Halloween day when this picture was taken, but the previous few nights were quite chilly. Her exposure time up to that point was already extending into several days and nights of what can only be termed “molluscan torture.” Although barely alive, she still had enough reserves to keep her valves (shells) shut. She yielded only slightly when I attempted to pry them apart (which I did only to make sure there was a living creature inside).

  Paper Shells are one of about 40 species of native mussels that live in the Great Lakes region. The waters of the Detroit River and Western Lake Erie are ideal environments for many types of these shelled creatures. Most mussels have thick rigid shells, but the Paper Shell has a very thin covering which cracks into pieces when the animal dies and the shell dries out – thus the name. On the living animal, light will transmit right through the shell and the fleshy creature inside (as seen here with a mid-morning backlight).

  Zebra Mussels, those alien mussels that have staked claim on all former native mussel territory, have inflicted havoc upon our local clam population. Because of this, natives such as the Paper Shell are worthy of some human sympathy. Wind tides are one thing, but alien biological tides are quite another.

  Since I couldn’t immediately purge the lakes of Zebra mussels, the only immediate favor I could render this clam was to toss it back into the drink. This was the least that a two footed creature could do for a one-footed fellow earth inhabitant. The water was some thirty feet away at the time and I made sure to plunk her an additional twenty feet out just in case.

  The water didn’t return to “normal” depth until yesterday. I doubt the mussel would have been able to stay clammed up for that long, but she probably has endured worse without my help.

November 1, 2008

Ghost Tracks

Filed under: Uncategorized — wykes @ 3:54 pm

 While minks are not actually vaporous spirits, they are ghost-like. They move along hidden wetland paths and rarely show themsleves. A mink sighting usually consists of little more than a chocolate brown flash. Such an encounter barely allows enough time to say, or think, “look, there’s a min…,” before the session is concluded. These elusive creatures also happen to be habitual wanderers who patrol large territories. Males can lay claim to several thousands of wetland acres or several miles of stream bank.  Females are more homebound, but 40 acre claims are not unusual for them.  Intercepting either sex at any single location within their stomping ground is therefore reduced to sheer chance.

  The usual methods for a curious naturalist to determine if mink are about is to hang around a wetland, in order to increase your chances of seeing one, or look for their tracks. By employing the first method I have been fortunate in seeing quite a few minks in the past few years.  Most of my glimpses have been just that – glimpses – but this past summer I was able to watch a nervous young animal pick away at the remains of a roadkill (see here & here). The slender figure eventually detected my presence and evaporated into the underbrush.

  Recently, I came upon the freshest set of mink tracks imaginable. They were in the form of a set of wet paw prints traversing over a metal culvert (see above).  The day being windy and relatively mild, it was obvious the maker had passed by only minutes before.  As I was taking the first photo, a movement to my right informed me that the tracks were actually only a few seconds old. A large male mink was walking the bank close to the water line only six feet away.

  The mink turned around and began to retrace its route.  I focused my camera on the wet tracks and waited for it to drift into my view finder (see here). Like an appartition, the creature suddenly appeared (see here) and looked nervously about.  I was positioned on a boardwalk overlooking the scene where he could not easily see me.  It seemed to be aware that something was amiss but chose not to look up. The fellow then melted away and was gone. My photo, like all spirit pictures, turned out to be slightly out of focus and ephemeral in nature.

  I lingered over the wet paw prints after the encounter and watched them dissipate. It took a little over a minute (see here, here, and here in sequence) before the culvert once again stood mute regarding the mink’s passage.

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