Loons are water birds known for their eerie, haunting calls that echo across lakes and ponds. The common loon is found across parts of North America and is the state bird of Minnesota. Loons make a variety of vocalizations throughout the year for purposes like communicating with other loons and defending territories. However, one question many people have is whether loons continue calling during the winter or if their calls fade away once colder weather arrives.
Do loons call in the winter?
Yes, loons do continue calling in the winter but their vocalizations are less frequent and less varied than during spring and summer. The common loon has four main calls: the yodel, the tremolo, the hoot, and the wail.
The yodel
The yodel is the most iconic loon call and is used primarily in late spring and early summer by male loons to communicate with their mate and chicks and defend their territory. Yodeling involves the male loon rapidly repeating a single note that rises and falls in pitch.
During winter, yodeling largely stops since loons are not on breeding territories. However, yodeling may still occasionally be heard in winter, just much less frequently than during summer.
The tremolo
The tremolo is a laugh-like call that is used all year round. It is often given when loons are alarmed or feel threatened. In winter, the tremolo may be heard if loons become distressed by the presence of eagles, humans, or other perceived threats.
The wail
The wail is a long, drawn-out call that sounds like a wolf howling. It is used in fall migration and continues sporadically through winter. Scientists believe the wail helps loons communicate and locate other loons while migrating or wintering on the ocean coast.
The hoot
The hoot is a short, soft call that loons give year-round. It is used frequently when loons are socializing with other loons. Hoots are given by loons rafting together on coastal waters in winter and help the birds maintain contact.
So in summary, the yodel and tremolo calls fade away in winter, but hoots and wails continue consistently as loons communicate and remain connected in winter flocks. The calls just become less varied and frequent.
Why do loons call less in winter?
There are a few key reasons loons reduce their calling during the winter months:
- They are not defending breeding territories – In summer, male loons constantly yodel to defend their breeding lakes from intruders. This purpose disappears in winter when loons vacate inland lakes.
- Energy conservation – Calling takes energy and winter is a time when loons need to conserve resources. Calling less helps them survive on limited food.
- Winter flocking behavior – On the ocean coast, loons gather in large flocks rather than as individual pairs. Less vocal communication is needed in tight winter flocks.
- Reduced need to communicate – Loons do not need to communicate with mates or chicks in winter. Vocalizations are focused on basic flock maintenance.
- Risk of attracting predators – Frequent calling could attract eagles or other predators in winter. Loons likely call less to avoid danger.
So in summary, loons call less in winter because they do not need to establish territories, conserve energy, flock together, have fewer social requirements, and want to avoid attracting predators. Their vocalizations become more targeted and strategic.
When do loons migrate?
Loons migrate from their inland summer breeding lakes to wintering grounds along both the Pacific and Atlantic coasts. Migration timing depends on the region:
Northeast and Midwest U.S.
In these regions, loons leave breeding lakes from October through November. They winter along the mid-Atlantic coast, Gulf of Mexico, and southeastern U.S.
Western U.S. and Canada
Here, loons leave summer grounds starting in September. They concentrate along the Pacific coast from southern Alaska to Baja California.
Interior Canada
Far northern loons leave first, starting migration in late August and September. Birds in central Canada follow in October and November.
So in general, most loons vacate inland lakes and start migrating between late August and November, depending on latitude. This seasonal movement is why loons are mainly only heard on lakes in summer. In winter, coastal areas become hotspots for seeing and hearing loons.
Spring migration back to lakes
In spring, loons undergo the reverse migration. They start leaving the ocean from March through May and arriving back at northern lakes to establish breeding territories and nest.
Where do loons spend the winter?
In winter, loons congregate along coastlines where they can forage in shallow, fish-rich waters. The three main wintering areas for North American loons are:
- Pacific Coast – From the Aleutian Islands of Alaska to Baja California. Greatest numbers off British Columbia, Washington, and California.
- Atlantic Coast – From Newfoundland to Florida. Most loons winter from New Jersey to South Carolina.
- Gulf Coast – Loons winter in coastal waters and bays from Florida to Texas.
Within these regions, loons favor certain habitat features:
- Shallow nearshore waters – Loons can more easily see and catch fish.
- Bays and inlets – These provide shelter from storms and ocean waves.
- Estuaries – Mixing of freshwater from rivers into ocean water boosts nutrients and fish.
Loons may also occasionally winter on large inland lakes if enough open water exists, especially along the Pacific coast and Great Lakes regions. But coastal areas support the vast majority of wintering loons.
How far do loons migrate?
Loons are strong fliers capable of migrating long distances between summer and winter grounds.
- Pacific loons – Migrate 3,000 miles between Alaska and Mexico.
- Common loons – Routinely fly 600-1,200 miles between inland lakes and the coast.
- Red-throated loons – Migrate enormous distances from Arctic Canada to Baja California, over 4,000 miles.
Tracking studies have recorded loons making nonstop flights of hundreds of miles over 1-3 days during migration. Their migration paths closely follow coastlines which provide rest and refueling stops.
Inland loons migrating to the coast have more challenging open-water crossings. Banding recoveries show loons banded on the Great Lakes later shot or found dead along the entire Atlantic coast into the Gulf of Mexico, showing their wandering winter movements.
How do loons adapt to winter?
Loons undergo several adaptations that help them survive harsh northern winters:
Plumage
In late fall, loons molt from their bold black-and-white breeding plumage into a dull gray-brown winter plumage. This cryptic coloration helps loons camouflage and avoid predation better in an ocean environment.
Weight gain
Before migrating, loons gorge themselves and build up fat reserves to survive periods of low food. They may gain over 40% of body mass.
Leg position
Loons can slide their legs far back on their bodies to reduce surface area exposed to cold water and conserve heat.
Reduced metabolism
In winter, loons lower their metabolic rate and body temperature by several degrees to conserve energy.
Feather density
Added feather density in winter increases insulation against freezing water. Loons may also tuck their head into their back feathers while sleeping or resting.
Do loons mate in the winter?
No, loons do not mate or bond with new mates during winter. They arrive on wintering areas already paired from the previous summer. Winter flocks consist of loons of all ages and pair statuses loosely aggregated for foraging.
Breeding activities like courtship, pairing up, establishing territories, and mating only occur during spring and summer back at northern lakes. The winter is simply a time for loons to survive until they can return to breeding lakes.
Some evidence indicates loons may re-pair with the same mate from previous years. Mate retention across years may be facilitated by wintering in the same region before returning together to the same breeding lake. More research is needed to determine whether loons ever switch mates from year to year.
How do loons behave in winter flocks?
On coastal wintering grounds, loons form large aggregations numbering dozens to hundreds of birds. These flocks are loose social structures with birds constantly joining and leaving.
Some key behaviors seen in winter loon flocks:
- Foraging together – Groups dive and feed cooperatively by herding fish.
- Roosting together – Loons float and rest together in rafts of hundreds of birds.
- Socializing – Loons preen each other’s feathers and give contact calls like hoots.
- Mobbing predators – Groups may act aggressive and jointly attack eagles or other predators.
- Bathing – Loons splash together in shallow waters near shore.
Overall, winter flocks help loons locate food and maintain social bonds during the nonbreeding time of year through communal behaviors.
How do loons find food in winter?
Loons are visual predators adapted to pursue fish while swimming underwater. On wintering coasts, loons need reliable sources of small fish to survive. They often target baitfish like herring, sand lance, smelt, and juvenile rockfish that school near the surface.
Key loon foraging habitats provide warmth and abundant prey:
- Estuaries – Warm, sheltered waters where rivers meet the sea.
- Upwelling zones – Currents bring cold, nutrient-rich water up from the deep.
- Power plant outflows – Warm water discharges attract fish in winter.
- Channel edges – Submerged structures concentrate fish.
Loons locate these fish hotspots and work together in groups to herd and capture fish near the surface. Their salt gland allows them to drink seawater and remain hydrated on the ocean.
In severe cold or storms, loons seek refuge in bays and inlets where they can still dive for fish out of the worst conditions. If oceans freeze, wintering loons are forced further south or even to land.
Do loons migrate at night?
Yes, loons typically migrate at night during both spring and fall movements. Nocturnal migration likely helps loons utilize cool air and tailwinds that develop after sunset. Their dark coloration may also help camouflage loons from predators at night.
Several advantages explain why loons migrate at night:
- Colder air reduces heat stress and water loss.
- Winds are often calmer with better tailwind assistance.
- Skies are frequently clear under high pressure systems.
- There is less turbulence from daytime heating.
- Predation risk is lower at night.
Loons may still migrate during daylight as well. But satellite tracking confirms loons disproportionately migrate around dusk, during the night, and before dawn when conditions are optimal.
Still, unfavorable winds or storms do sometimes force loons down or cause them to pause migration for days to weeks. These loons often wait out storms close to shore before resuming movements under better skies.
Conclusion
In conclusion, loons do continue calling in winter but at lower rates and with less variety than their iconic summer yodels and tremolos. Wails and hoots predominate on wintering grounds to maintain social contact and cohesiveness in flocks. While not mating, loons cooperatively forage, roost, socialize, and mob predators while gathering along coasts to survive the harsh northern winter. Their migrations and adaptations allow loons to endure cold and storms until spring returns them to northern lakes and another breeding season.
