Freshly
rain-washed sunshine sparkled on the lake as a slight breeze ruffled the
surface. We couldn’t have asked for better weather. But we sought more than
just a lovely pontoon ride on Lake Namakagon. We were on the lookout for loons.
By my estimation, loon chicks should have hatched on the lake! Last year the lake hosted three successful
nests, and we enjoyed watching the chicks’ antics throughout the summer.
This
year, spring weather posed a bit of a challenge for loons. First, late winter
blizzards and cold temperatures kept the lakes frozen much later than normal.
Loons migrating north from the Gulf of Mexico had no way of knowing this, and
they backed up on ice-free lakes to the south, just waiting for their chance to
get back to their old territory or claim a new one. With hormones raging in
expectation of mating season, territorial aggression may have caused energy-depleting
skirmishes even as loons wait to head north.
As
the lakes slowly opened, loons made a break for it, many of them migrating on
the night of May 2nd. Unfortunately, an ice storm turned deadly. Marge Gibson runs the Raptor Education Group
(REGI) wildlife rescue center in Antigo. “The loons were iced,” she explained. “They
were flying at altitude and the birds became wet, and basically were encased in
ice, and then fell to the ground like missiles from a high altitude. Many of
them were actually injured.” REGI took in 57 stranded or injured loons in just
three days. Most of those were rehabbed and released. Loons not rescued were
probably not so lucky. No one really knows the extent of the damage to the loon
population.
Finally,
the ice on Lake Namakagon went out on Monday, May 13. That Friday I spotted a
few territorial pairs who had migrated back to their usual places on the lake. Courtship,
pair bonding, nest building and mating can take a few weeks. Then, once the
male has chosen the nest site, the female has built the nest, and they’ve
copulated on the nest, it takes another couple weeks before the female lays her
two eggs.
With
only one working ovary, the loon female can only lay one egg at a time, about
1-3 days apart, so the chicks hatch at different times, too. The loon parents
share the incubating duties equally for at least 26 days before the first egg
hatches. Then it takes about a day for the chicks’ feathers to dry out enough
so they can float.
So,
by my calculation, today was about the soonest we would expect to see chicks on
this lake.
Our
first stop on this Loon Pontoon Tour was Sugar Bay. This beautiful, shallow inlet
hides behind Anderson Island, and is only accessible by going under a bridge. For
the past two years this pair has nested successfully. So it was with great
anticipation that we puttered around the nesting bay, and then back into the calm,
weedy area the loons use as a nursery.
A
dark silhouette of a loon appeared out in the nursery, and we cautiously
motored over. Then, another loon appeared near it. As we drew close, it became
evident that they were alone. I sighed in disappointment. At this time of year,
either the chick should be with the parents, or one parent should still be on
the nest. They may still try a second nesting attempt, but laying eggs this
late in the season does not give the chick much time to gain strength before it
must migrate in November.
With
a little disappointment, and a little hope, we turned and headed up to another
remote corner of the lake that often hosts a successful nest. Jackson Lake is
connected to the main lake by a beautiful, narrow channel filled with water
lilies, beavers, great blue herons, and tamaracks. As the view into the wider
part of the lake opened before us, we spotted the pair almost immediately. And
one loon seemed to have an oddly shaped back…
A
crisp view through binoculars revealed a single fluffy chick bumming a ride.
Success! The entire crew on the pontoon was elated. Chicks can swim and dive as
soon as their feathers are dry, but they tire and chill easily, so catch rides
for about their first three weeks of life. This also helps protect them from
swimming predators (musky, northern pike, and snapping turtles), and flying
predators (eagles and gulls.)
As
we watched, the chick slipped into the water, and the parents began to hunt.
The adult loon dipped its face into the water; an action called “peering” that
allows it to see underneath the surface glare. Then, with submarine-like
stealth, it dove. Within a few seconds (the average loon’s dive is only about
45 seconds) the parent popped back up with a minnow cross-wise in its beak.
With surprising speed, the tiny chick paddled over to meet the parent,
stretched its little neck out long, and gobbled its catered lunch!
At
this stage, chicks eat minnows and aquatic insects. Adults (who weigh about 10
pounds) can eat about 2 pounds per day
of smaller fish like perch. Over the summer, a loon family of four will eat about
a ton of fish. For reference, a 150 pound human on a winter camping trip eats
about 2 pounds of food per day.
We
watched for several minutes as the family calmly continued the feeding
operation. If any of the loons had given the tremolo alarm call or acted
distressed, we would have left immediately. Luckily, loons are learning to be
tolerant of humans in boats, and on this lake at least, we rarely cause them to
show alarm.
Finally,
we had seen enough, and bird-watched our way back to the landing. Spirits
soared all around, as we cheered for the loons’ successful hatching, and our
successful viewing. Come join me for another Loon Pontoon, held Thursday
mornings throughout the summer!
For over 45 years, the Cable Natural History Museum has
served to connect you to the Northwoods. Come visit us in Cable, WI, at 13470
County Highway M. The current exhibit, “Deer Camp: A Natural and Cultural
History of White-tailed Deer,” opened in May 2013 and will remain open until
April, 2014.
Find us on the web at www.cablemuseum.org to learn more
about our exhibits and programs. Discover us on Facebook, or at our blogspot,
http://cablemuseumnaturalconnections.blogspot.com/.
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