An online resource based on the award-winning nature guide – maryholland505@gmail.com

Posts tagged “Gavia immer

Juvenile Common Loons Molting For A Second Time

When Common Loon chicks first hatch, they are covered with down and look like sooty black puffballs.  These feathers are pushed out when the loons are 10 to 14 days old by a second plumage of brownish-gray down feathers.  When the young are about a month old, these feathers start to be replaced by juvenal contour feathers. By the time the young loons are 10 or 11 weeks old, their down feathers are mostly gone and their juvenal plumage is nearly complete. This plumage is very similar to the winter plumage of adult loons. You can tell the difference between the two by the whitish-gray tips of the juveniles’ feathers, which the adults lack.  (Pictured juvenile loon is about seven weeks old, showing remnants of the second down plumage.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loon Chicks Riding High

July on a lake occupied by nesting Common Loons is a birder’s slice of heaven.  Eggs are hatching, day-old fluff balls are riding high on their parents’ backs, parents are busy catching and delivering small fish and crayfish to their chicks, and survival lessons are being given. Recently while watching a pair of two- or three-day-old chicks whose parents were off obtaining their offspring’s next meal I observed a juvenile Bald Eagle, known predator of Common Loon chicks, soaring overhead.  Within a split second both loon chicks dove and stayed submerged long enough for the eagle to give up the ghost. Nature or nurture?

To see a related entertaining phenomenon, go to https://loonproject.org/2019/06/29/unlikely-allies/?fbclid=IwAR0po44dJaElcyYpqKqLwaz9A6gs7RxWfhJRkoB-QleC7sUGnjgElksR5G4.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Image

Five-day-old Common Loon Chick Seeking Shelter & Rest

6-27-18 common loon chick3


Common Loon Chicks Hatching

6-27-18 loon chicks3_U1A9901

Newly-hatched Common Loon chicks can swim as soon as they hit the water, which they do as soon as their down dries after hatching, usually within 24 hours. Their buoyancy and lack of maneuverability, however, leave them vulnerable to predators. Parents usually don’t stray far from their young chicks due to the omnipresent threat of eagles, hawks, gulls, large fish and snapping turtles.  During their first two weeks, young loon chicks often seek shelter (and rest) on the backs of their parents.

Naturally Curious is supported by donations. If you choose to contribute, you may go to https://naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loon Chicks Riding High

7-10-17 common loon and chick IMG_4179

Why do Common Loon chicks ride on their parents’ backs for the first two weeks of their life? There are several reasons. Loon chicks leave their nest as soon as their downy feathers are dry; if they stayed in their ground nest, they would be very vulnerable to predators on land. For the same reason, they rarely return to their nest.

Like many young birds, loon chicks can’t immediately regulate their body heat.  Many birds brood their young in the nest, providing them with warmth and shelter.  Common Loon parents brood their young on their back (and under their wings). On windy, cloudy, cool days, the chicks are nowhere to be seen, huddled under their parents’ wings. On calm, sunny days, they are in full view.

Although they can swim immediately after hatching, loon chicks are very buoyant and have difficulty maneuvering. Predators such as Bald Eagles, Common Ravens and gulls are quick to prey on young loons that have no parental protection. In addition, predatory fish such as Northern Pike and Largemouth Bass are a threat. Once they are several weeks old, the chicks are not only bigger, but they are more mobile and can avoid predators more easily.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.

 

 

 


Common Loon Chicks Growing & Acquiring Survival Skills

7-13-16  common loon chicks2  361 A great deal of learning is packed into a Common Loon chick’s first week.   It learns to ride on its parents’ backs as well as crawl under their wings, a necessity due to its vulnerability, lack of maneuverability, inability to regulate its body temperature.  Communication skills are practiced, with soft “mewing” elicited when a chick is hungry or in need of attention.  The act of preening begins, and the chick successfully retrieves small fish and crayfish from its parents’ beaks.

By the second week, Common Loon chicks are still fluffy balls of down, but they molt a second time, after which they are a much lighter brown.   They dismount from their parents frequently and motor around under their own steam, usually staying very close to a parent.  By the time they are ten days old, their hitchhiking days are over for the most part, and they are on their own when it comes to getting from one place to another. The eleven-day-old Common Loon chicks pictured are just starting to make shallow dives at this point in their development, but still depend largely on meal delivery from their parents.  In another month, they’ll be catching most of their meals themselves, although their catches will be supplemented with food provided by the parents.  In two months their flight, as well as contour, feathers will have replaced their down feathers, and within a couple more weeks of that happening, they will be capable of flight.

(The next Naturally Curious post will be on 7/18/16.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com   and click on the yellow “donate” button.


Common Loons Returning

common loons back IMG_7494

After spending the winter along the Northeast coast, adult Common Loons are returning to their New England breeding ponds and lakes.  Evidence indicates that photoperiod determines the general timing of their northern migration.  Loons are well known for arriving at their breeding lakes soon after ice out (often returning when lakes are only partly open). How do they time their return so precisely?  Loons often congregate in open bodies of water, including rivers, as they proceed northward. Once they approach their breeding grounds, reconnaissance flights are made from open water to territorial waters to see if the ice is out. Once it is, their migration continues.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com   and click on the yellow “donate” button.

 


Avian Air Sacs

7-10-15  sinking loon2  482Birds have a very efficient breathing system which makes use of their lungs, but also utilizes air sacs (7-12, depending on species) within the bird’s body. Common Loons use their air sacs for more than respiration, however. By changing the amount of air in the sacs, loons can vary their depth while resting in water. A deep breath fills the sacs with air and produces high flotation. During dives, in addition to compressing their feathers(which forces air out from between them), loons decrease the amount of air in their air sacs by exhaling. The ability to deflate their air sacs also allows loons to quietly sink below the water’s surface in order to make it easier for their young chicks to climb aboard.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Recently-hatched Common Loon Chicks Stay Close to Parents

7-1-15   loon and chick  332The first few days of life for Common Loon chicks can be quite precarious. As soon as their down dries, the chicks are quick to leave their nest and enter the water, where they are not as vulnerable as far as land predators are concerned. However, there are dangers there, as well. Young chicks are exceptionally buoyant, and have difficulty maneuvering in the water. Parents must keep a close eye on them, so as to protect them from predators both above and below the water, such as Bald Eagles and Largemouth Bass. For the first two weeks or so parents provide protection for their young by ferrying them around on their backs much of the time. (Note egg tooth still remains on this two-day-old chick.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loons Migrating

10-27-14 common loons migrating2  146Most of the eastern U.S. and Canada Common Loon population shifts from freshwater inland breeding locations to coastal marine wintering areas, although some remain at inland freshwater sites throughout winter. Research shows that the very large loons in Maine, New Brunswick, and eastern New Hampshire do not migrate far and primarily overwinter in the Gulf of Maine, while smaller loons from other New England and New York breeding populations migrate to Long Island Sound south to New Jersey.

Some Common Loons begin their diurnal migration to their wintering territory in late summer, but most loons leave their breeding territory in September (high latitudes) and October (low latitudes), and arrive at their destination by the end of November. Breeding pairs and their offspring do not migrate together. Parents generally migrate first, usually separately; young remain on their lakes after adults have departed, until near freeze-up, and often migrate in groups. Although they often migrate singly, common loons do form groups (in some places, hundreds or thousands of birds) on large bodies of water before and during migration. These are referred to as staging areas. When migrating over land, loons can reach an altitude of a mile and a half; over water they usually fly within 300 feet of the surface of the water.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Two-month old Common Loon Chick Beginning to Look Like a Loon!

8-12-14 c.loon two months old IMG_8704Remember that little black ball of fluff that was featured in Naturally Curious loon posts two months ago? That downy Common Loon chick has lost both its black and its brown coat of down, and is now covered with smooth, gray contour feathers. Nearly the size of its parents, it is looking quite sleek. Soon the chick’s flight feathers will be completely in. In only a matter of two or three more weeks it will be flapping its wings and making take-off runs in preparation for flight, which it will be capable of in another month. (It will be two years old before it attains adult plumage.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loon Chick Update

7-16-14 loon update2 187The fluffy, black loon chick that was the subject of Naturally Curious posts a couple of weeks ago is a month old this week (original photos were taken several days before posting), and it has undergone several transformations. Two weeks ago the black down of the newborn chick was replaced with a second coat of down that is brown in color. Between three to four weeks of age, its body elongated and its bill began to lengthen. In another week or so, the first gray contour and flight feathers will begin to replace the down, a process that takes about three weeks.

Both parents are very attentive and are providing as many fish and crayfish as the chick can consume, sometimes making the chick dive for its meal, sometimes not. Because one egg failed to hatch, the lone chick receives all of both parents’ attention, guaranteeing a full stomach. It isn’t unusual to see both parents dive, come up with fish in their bills, and deliver their catch simultaneously to their chick.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loons: Feeding Chicks

7-4-14 loons feeding 202Both parents provide their young with food (small fish, crayfish, etc.) several times an hour, especially early and late in the day. (This practice continues, in a more limited way, long after the young loons can provide for themselves, right up until the parents migrate — before the juveniles — in the fall.) Often food delivery takes place when the chick is in the water, but occasionally it occurs while the chick is on the parent’s back during its first week or so of life. Initially the adult loon catches prey, swims up to its chick while holding the prey in its beak until the chick grasps it and swallows it. By the third week, the parents start dropping the fish or crayfish in the water in front of the chick, forcing it to learn how to catch its own food. Needless to say, in the beginning, the adults must have great patience, retrieving and dropping the prey time after time while the chick acquires the skills necessary to catch it. (Photo: Adult with fish approaches mate while making a soft mewing sound. Mate raises wing, chick emerges and reaps the benefit of home delivery.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loons: Brooding Chicks

7-2-14 common loon with chicks-broodingIMG_3215While loon chicks can swim as soon as their down dries, they are not able to regulate their body heat for their first two weeks of life and are dependent upon their parents for warmth. (A lot of the chick’s heat is lost through its feet when it is in the water.) Whereas most birds provide this warmth (in a process called brooding) in the nest, Common Loons brood their young on the water during this period. The chicks simply climb up the backs or sides of a parent while the parent raises its wing. Once the chicks are situated on the back of the loon, the adult lowers its wing, sheltering the vulnerable chicks from the elements. If the sun is out, the wind is slight and the temperature is warm, the chicks will come out from underneath the wing(s) and ride around enjoying the view. If the wind picks up or the temperature drops, the chicks will crawl back under their parent’s wings, totally hidden from view.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loons: Egg-laying & Incubation

7-1-14  Loons #2 - incubating 404Typically Common Loons lay two eggs, each of which is roughly four inches long and olive green to brown in color, with brown or black splotches. The eggs are laid one to three days apart with the 28-day incubation period beginning when both eggs have been laid. Both parents incubate, turning the eggs when they switch places or during long periods of incubation. If the loon on the nest is anxious for relief, it will give a “wail” call, and if its mate does not respond, it continues wailing, even after leaving the nest to find its mate.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loons: Nest-building

6-30-14  Loons #1 - nest building 496Naturally Curious posts for the next four days will be devoted to Common Loons. They are nesting now, eggs are hatching, chicks are swimming, parents are feeding – life is good on ponds and lakes in the north woods, and I would love to share this magical time with you.

Both members of a pair of Common Loons contribute to nest-building in May or June. Their ground nest is often built on the sheltered side of an island, facing the mainland. It is usually within just a few feet of the water, eliminating the necessity for the loons to walk very far. (The position of their legs far back on their bodies is advantageous when it comes to diving and swimming, but makes walking very challenging.) Both male and female share the building of the nest, throwing submerged vegetation from the water onto the nest site or pulling it from the water while sitting on the nest. Material continues to be added to the nest throughout incubation. Nearly two feet in diameter, a nest can take a week or so to build. Successful nests (those that produce chicks) are often re-used from year to year.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loons Molting

9-30-13 molting loon MH_20091004_214955_3Loons begin a full body molt (minus their wings) in the late summer and early fall, prior to migration. The black and white breeding plumage of adult loons in summer is replaced by the gray-brown of winter. This process typically begins at the base of the bill and spreads across the head and over the upper back. The process of molting can extend through migration on into December.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Common Loon Chick Meal Delivery

7-10-13 loon chick being fed 119For the first few days of a loon chick’s life, both of its parents are ever-present, catching and delivering small fish, crayfish and invertebrates for their one or two chicks. Their initial buoyancy and their lack of experience prevent the chicks from procuring their own food for the first month or so, although they soon learn how to chase fish. During the first couple of weeks, the parent loon, having caught a crayfish, small fish or other prey, swims right up to its young and offers the chick its next meal. The chick grasps the food while it is still in its parent’s beak. The parent lets go, and the chick attempts to swallow the crayfish (in this case). In the beginning, the chick often drops its meal. The parent then dives down to retrieve it and once again offers the same crayfish to the chick. This sequence of events can happen over and over until the chick finally manages to hold onto and shift the crayfish into a head-first position in order to swallow it. By the third week this beak-to-beak service begins to be replaced by a practice designed to teach the chick how to capture its own meals. The parents start dropping the food they’ve caught for their chick into the water in front of them, forcing the chick to dive and develop the skills necessary for survival. (The pictured loon chick is well into its second week. Close examination reveals that the chick’s “egg tooth,” used to exit the egg, is still present at the tip of its beak. By week #3 it is not evident.)


Common Loons Nesting

6-13-13 loon on nest 457Generally speaking, Common Loons return to northern New England from their coastal wintering waters sometime in April or May. Males and females pair up after they arrive at their ponds, and several weeks later they breed and build a new nest or renovate an old one, with the male choosing the actual nest site. Successful nests sites are often reused from year to year, especially if the male returns. Protection from wind, waves and predators is paramount. Because their hind legs are positioned so far back on their body, loons are awkward walkers, at best. Thus, they usually build their nest adjacent to water so that they can easily slip onto and off of it. The nest is constructed during the day by both adults and is made of vegetation that the loons collect close to the nest. A loon often sits on the nest while collecting material, stretching its head down into the water in order to retrieve vegetation which it then places on the nest. Two eggs are laid, usually between mid-May and early June. After being incubated by both parents, the eggs hatch in roughly 28 days. As this photograph indicates (egg just visible below loon’s body), material continues to be added to the nest during incubation.


Aging a Common Loon Chick by its Plumage

This year’s Common Loon chicks are now roughly two months old.  Even without being aware of when it hatched, you can estimate the age of a chick by looking at its feathers.  Their color and type (down or contour) can give you a good idea of how many weeks old it is. Common Loon chicks are born covered with sooty-black down.  By the time they are three weeks old they have replaced this natal down with a second (gray-brown) down.  Juvenal feathers start appearing soon thereafter, replacing the down — the age of a chick can be estimated by the amount of down that remains.  By eight weeks of age the chicks have just small tufts of brown down remaining on their head and neck (see photo).  By nine weeks of age their entire body, including their head and neck, are covered with smooth, gray contour feathers and there is no sign of down.


Great Northern Loon Eggs Hatching

Like many flowering plants that blossomed two or three weeks early this year, Great Northern Loons (previously called Common Loons) got an early start to their nesting season. While some adults are still sitting on eggs, some chicks can be seen hitching a ride with their parents. Even though chicks can swim as soon as their down dries, their inability to regulate their body temperature for the first two weeks and their need for protection from predators at this vulnerable time, they are brooded on the backs and under the wings of their parents. After a couple of weeks, however, the chicks are under their own steam and can be seen bobbing in the water near their parents.  (Kayakers and photographers — extreme caution should be taken to avoid approaching loon nesting areas too close at this time of year.)


Common Loons Returning to Nesting Lakes

Recently Common Loons have been seen on several Vermont lakes and ponds.  Spring arrival on nesting lakes depends largely on the timing of ice-out. During migration, Common Loons have what are called “staging” areas — lakes as well as rivers, where many loons congregate as they proceed northward (southward in the fall). Reconnaissance flights are usually made from open water north to territorial waters to see if the ice is on its way out.


Common Loon

Since hatching in July, the downy, sooty black common loon chick has matured in to a sleek, brown juvenile, close to its parents in size.  Even so, adult loons are still caring for and feeding their young, though far less so than earlier in the summer, as juvenile birds are now foraging on their own.  Roughly nine weeks old, the young bird accompanying its parent in the photograph will be airborne in three weeks or so, but for the most part will remain on its natal pond or lake.  Juveniles typically don’t leave for their salt water wintering grounds as long  as there is open water — long  after their parents have migrated.