Snow squalls, hot chocolate, and...loons!  Fall monitoring on the Squam Lakes

By Tiffany Grade

Hot chocolate was always on hand as LPC collaborated for the second year with our colleagues at Biodiversity Research Institute (BRI) in Portland, ME, on a study of fall departures of loons from lakes in New England.  As with so much else in loon biology, basic questions about fall migration remain unanswered:  How long do loons with chicks stay in their territories before departing?  Do the parents continue caring for the chicks into the fall?  Do male loons depart first or do females? 

Answering these questions requires bone-chilling days monitoring loon pairs twice each week until the loons decide it's time to head to the waters off the New England coast.  This fall, I monitored three loon families on Big and Little Squam Lake--one family had two chicks and the other two had single chicks.  The hatch dates of the chicks--a month apart between the oldest and youngest chicks--made for an interesting contrast in behaviors and departures, particularly considering that the youngest chick didn't hatch until July 31st.       

Fall loon watching allows the observer to see loons in very different ways than summer loon watching, even to the extent of where loons spend their time.  As the human activity on Squam diminishes and the lake empties of boats, it becomes disconcertingly evident how much boating activity pushes loons away from fully utilizing the resources of their territories.  With boats gone, loons quickly take advantage of feeding, resting, and preening opportunities in the active boating areas that they avoid during the summer months.  This behavior was a stark reminder of the need for lake users to respectfully share lakes with loons.

As fall draws on, at least on Squam the males seem to become the "primary care-givers" for the chicks while the females wander more widely to the fringes of the territory and beyond.  (Many of Squam's loons are banded, so we know the sex of these loons).  Preliminary data from smaller lakes suggests the females seem to stay with the chick longer and are the last to leave, but much more data is needed to see if there is a pattern or if it simply varies among individual pairs.  It is amazing to see how closely some of the chicks continue to follow the males, as well as the differences in individual behaviors between chicks.  In the two-chick family, one chick was very independent--it only rarely re-connected with the male and its sibling.  I would often see it off by itself on the fringes of the territory, diving and feeding.  Even if it was near the male, it would not come in for food.  Meanwhile, its sibling was always right next to the side of the male, constantly begging for (and receiving!) food.  Within one family, these two chicks demonstrated the extremes of chick dependence on parents-even when those chicks were upwards of four months old.

Even though this chick is capable of catching fish on its own, it is happy to receive a hand-out from its father.  Photo courtesy of Donald Grade.

 Late summer and fall is a season for socializing for adult loons-the chicks are more independent (unless you have a clingy one!), hormone levels for territorial defense are decreasing, and loons can afford to visit with other loons.  However, as I saw, if one of those visitors gets in the vicinity of a chick, a day in October can look like a day in July.  On several occasions, I witnessed parent loons interacting in a very social manner with other loons; but, as soon as the groups approached the vicinity of the chicks, the parents became defensive, splash diving vigorously, and escorting the other loon(s) out of the territory, just as they would have done to protect a downy chick in July.

Nor was it only the parent loons who were playing defense-chicks did as well.  When another chick began tagging along with the single Squam chick and its parent, the resident chick began aggressively asserting that s/he was the rightful chick in the territory.  S/he asserted primacy of position with the male parent s/he was with, and eventually began splash diving and trying to drive the other chick off.  The male yodeled but otherwise did not interfere with the encounter.  Eventually the resident chick succeeded in driving off the other chick, but it was fascinating to see chicks already using some of the behaviors and posturing they will use to defend their territories as a member of a pair, which likely won't happen for another six years. 

By early November, the two families with the older chicks had left.  In both cases, the females left first, followed by the males, and the chicks were gone within days of the last parent leaving.  But the family with the youngest chick hung on, unwilling to leave the beautiful waters of Squam despite snow storms, high winds and waves, and ice forming in my gas line, my veins, and the side coves (my thanks to the Squam Lakes Association for using their barge as an ice-breaker for me!).  My last visit to the lake was November 25th, when, after finding the territory of that youngest family vacant, I saw the male amidst the tossing waves outside his territory.  By mutual consent, LPC and BRI decided it was time to hang up the boat keys for the season.  It was bittersweet as I broke through the ice by the dock for the last time in 2014: sweet, as I anticipated the hot chocolate that was becoming increasingly necessary in increasing quantities to thaw me out; bitter, as I wondered how the offseason would be for Squam's loons and fretted about whether or not they would survive to return.  LPC had fitted this last male I saw with a geolocator on his band this past summer.  If he returns to Squam next year and we recapture him, the geolocator will tell us where he spent his winter (within a 75-mile radius) and the date he actually left Squam--all from the warm comfort of our office, no hot chocolate needed!  But exactly how he spent his winter will remain a mystery.  At least I got to see his last efforts ensuring his chick made it off Squam with a strong dose of parental care to help it on its way.

A geolocator is attached to a loon's band which will help track its movements through the winter.  Photo courtesy of BRI's Adirondack Center for Loon Conservation.