In roughly one-fourth of the struggles the losing male dies either by being drowned or from puncture wounds. Territory is so important that males go beyond the types of threat displays seen in other species, to actual combat. The reasons loons so loudly announce their presence, both day and evening, is that to raise a family, each nesting pair needs exclusive use of 50 to 100 acres of pond or lake to catch the 1,000+ pounds of fish and other foods needed for breeding and chick raising. The nature writer John McPhee reflected, “If he were human, it would be the laugh of the deeply insane.” The major calls are yodel (males only), wail/howl and tremolo. Loons are best known for their vocalizations, which can be heard for distances of a mile and more. It has been incorporated into “life history theory.” For nascent naturalists, both theories are well-defined at Wikipedia. Scientific support for r/K theory has declined since first proposed back in the 1970s. In contrast, Atlantic cod produce more than 1 million eggs each year and provide no parental care.
A loon pair will produce one or two eggs each year, with roughly 50 percent surviving to fledging (flying). Both modes have evolutionary advantages and disadvantages. The other end of the spectrum, r-selection, describes high reproduction rate, low survival percentages and a short lifespan. K-selection describes a low reproduction rate combined with parental investment in caring for infants, a high infant survival rate and a long lifespan. Loon reproduction fits into the K-end of r/K selection theory, a means of describing two reproductive strategies. If both birds of last year’s pairs show up at the same body of water they will stay together, but if one of the pair does not, a replacement loon will move in. Loons often return to the same body of water they left in the fall, especially if they succeeded in raising chicks there in past years - males first, to claim the territory, then the females. The common loon worldwide population is estimated at about 600,000 birds, with perhaps 30,000 nesting in the contiguous 48 states. around the Great Lakes and northern New England.
Breeding territory is across Canada and Alaska, with the southern edge of the range extending into the U.S. The species we see in the northeastern United States is the common loon. There are actually five species of loons: common, yellow-billed, black-throated, red-throated and Pacific. Loon use their webbed feet for propulsion, whereas penguins – faster swimmers – use their wings. Loons dive for 30-60 seconds versus 5-20 minutes for penguins. Otherwise coming up short (or tall, depending on which penguin species is up for comparison). Swinging, monogamish, polyamorous/polyfidelitous, and anarchistic relationships can all be considered “open.The common loon is a northern hemisphere’s failed attempt at approximating a penguin. Generally rooted in specific rules, expectations, and communication between those involved, open relationships may take a variety of forms and may evolve over time as needed to meet the needs of those persons involved. A couple practicing this relationship type might engage in sexual activity with the secondary partner together or separately, or they may each have independent outside relationships with different secondary partners-regardless of the specific parameters, the primary couple always remains a priority. The most common form of open relationship is that of a married or long-term committed couple that takes on a third (or sometimes fourth or fifth) partner whose involvement and role in the relationship is always secondary. Open relationships are varied enough to be an umbrella term for consensually non-monogamous relationships based on a primary couple who are “open” to sexual contact with others.
0 kommentar(er)
