the trustees of reservations
On The Land
The Trustees of Reservations

Tuesday, March 25, 2014

CATerwauling bobcats and "Extra-Vernal" pools!

Our favorite ridgetop vernal pool does not in fact remain "vernal" most years - it usually holds water year-round, serving as an important water source for resident and transient wildlife - it seems almost appropriate to rename it our "extra-vernal" pool since it doesn't typically go away after spring or even summer.  Although it is not a "certified" vernal pool by the state Natural Heritage & Endangered Species Program (NHESP), the obligate species' egg masses of wood frogs and salamanders that we observed during last year's exploration indicate that it is "certifiable", meeting other criteria too like having no flowing outlet and no fish population.  While winter is holding on tenaciously this year, soon it will melt down, the "quacks" of wood frogs will fill the warm spring air, and salamanders will congress soon to lay their eggs during a warm and rainy "Big Night!"

The pool is quite full in the springtime during our 2013 Vernal Pool Exploration workshop!
So what happens when you have an "extra-vernal" pool tucked into a low spot along the high ridge of a forested hill, rich with food sources too like mature mast-producing trees including beech and red oak?  Our wildlife cameras were set up to find out, and show many mammals of this forest predictably coming by for a drink and perhaps some beech nuts, but also for some unpredictable frolicking!  Our past post linked here will show you some videos of bears who came for a drink and stayed to play! 

Our vernal pool, quiet in winter except for a photo-bombing squirrel and some porcupine-chewed hemlock twigs!
Late winter is a quiet time at our pool - the surface is frozen solid, the highbush blueberry bushes stand bare and the winterberry holly shrubs are, too, stripped of their bright red late-fruiting berries by hungry birds.  At this time of year, the pool is not much of a water or a food source.  On an early February visit, we did not see signs of much action in the fresh coating of snow as we circled the pool.  One deer had ambled by and bedded just east of the pool for a cold night on the ridgetop.  We found a set of porcupine tracks coming up from the eastern face of the ridge, leading towards its favorite trees to climb - a couple hemlocks and a red maple surrounding the pond.  As we approached what appeared to be the porcupine's favored hemlock, tell-tale twigs littering the ground, another set of tracks intersected hers out of the mountain laurel - small and delicate, with clear indentations of four toe pads, a three-lobed plantar (heel) pad behind it, and no claw marks.  

Perfectly-defined bobcat tracks by the vernal pool!
Bill Lattrell was with us that day, a tracker and ecologist and friend of the CR Program (and fellow blogger! take a read by clicking!), who was helping us to scout the area for an upcoming wildlife tracking workshop, and to place a couple wildlife cameras in new places.  He confirmed that these were bobcat tracks, and some of the best he had ever seen!  If it excited Bill, we knew that we were witnessing something special.  We followed the tracks out of the mountain laurel thicket and over towards the pool - the set of tracks took a sudden bound, looking like the cat pounced toward a hemlock, perhaps after a mouse, pivoting itself back off the trunk in the direction it had come, and sliding to a stop!  Just past the tree, we realized something even more interesting was afoot- a second set of bobcat tracks joined the first!

A second set of tracks (top right!) SLIDES in to ambush the first set!
Known as solitary animals, there were only a few things this could mean.  Bill quickly hazarded a guess, as the two sets of tracks went out on the ice, danced over a log in the middle of the pool, and slid playfully out toward the middle!  The tracks doubled back towards the log, and evidence of an animal laying down and depressing the snow was visible. His guess?  That we were probably seeing the courtship dance of two bobcats about to mate!   Known for pursuing and ambushing one another, and sometimes even becoming aggressive to each other before mating, the sliding and rolling of the two bobcats, observed on the frozen pond and by the log, suggested that this was the answer!  It was early in their breeding season (most common in February through March in southern New England), but not too early - plus we were near likely resident bobcat habitat with south-easterly facing slopes with steep rock ledges and overhangs.  We decided to put the camera facing right out towards the playful felines' spot, then waited patiently for a few weeks before returning to check.  Bill even recommended camping near the pool, to hear the unearthly "Caterwauling" yowls that bobcats make - we never got around to it, but sometimes it's just better to give the wild a break from our presence.

The kitties came back!  Click for the full-size photograph.

This one in a million photograph of two bobcats was the amazing result of our previous scouting!  

We plan to leave the bobcats alone for a couple more weeks, until Saturday April 12th.  We're guessing they've moved on anyways, expecting kittens!  Please join us that day (and on the evening of Thursday April 10 for an introductory presentation on vernal pools!) for our second annual CR Program vernal pool exploration in partnership with Hilltown Land Trust.  The pool will be (hopefully) thawed and the wood frogs and salamander eggs freshly laid.  We'll be joined by Bill Lattrell to guide us in what we find.  See flyer below, and you must RSVP to register.