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Marbled Murrelet Marbled Murrelet The ancient mossy trees in which these birds nest are disappearing. Ministry of Environment, Lands and Parks Marbled Murrelet in British Colum- own designations: Threatened in Wash- bia. Because this trend is likely to con- ington; Sensitive in Oregon; Endan- tinue for some time, the species is gered in California. Forest harvesting clearly at risk. has apparently caused serious murrelet Why are Marbled Murrelets declines in the Pacific Northwest states. at risk? What is their status? In British Columbia, some nesting he Marbled Murrelet, a small, north he Marbled Murrelet lives along the habitat is protected in national and Pacific seabird, needs coastal old- Pacific coast of North America from provincial parks, recreation areas and growth trees in which to nest. In the Aleutian Islands to central ecological reserves. However, the bulk of T British Columbia, and elsewhere in T California. The bulk of the popula- the murrelet population nests in forests the murrelet’s breeding range, these tion is found in Alaska, with populations having little or no protection from ancient, mossy giants are disappearing. estimated at 220 000 birds. Based on future logging. The British Columbia Much of the low and middle-elevation extrapolation from a few surveys at sea, Wildlife Act provides protection for forest has already been cut and murrelet the British Columbia population has active nest trees, but not for the sur- populations have probably already been estimated at 45-50 000 birds. About rounding forest. Very few nests have declined from 5500 are present in Washington, been located and finding more promis- historic levels. As 15-20 000 in Oregon, and 6500 in es to be a very difficult and laborious logging spreads The Canadian California, for a total population process. Since murrelets seldom re-use into more re- population of 280-300 000. a nest or nest tree, they require a wide mote coastal val- The Marbled Murrelet is de- selection of potential nest sites to main- leys, populations was designated fined as a “Migratory Non-game tain a viable population. are likely to Threatened Bird” under the federal Migra- decline in pro- tory Birds Convention Act. This What do they look like? portion to the by protects the birds, their nests he Marbled Murrelet (Brachy- amount of nest- in . and eggs from wilful damage ramphus marmoratus) is a small, ing habitat that is throughout Canada and the plump seabird, about 25 centimetres lost. Original United States. The British T long, belonging to the auk family or forest is replaced with second-growth Columbia Wildlife Act, and various state Alcidae. When swimming, its slender that mostly will be harvested every 80 laws, give similar protection. black bill and stubby tail are usually to 100 years, never allowing the trees The Canadian population, confined tipped upward. In its rather drab breed- to reach the age, size and form that entirely to British Columbia, was ing season plumage, the top of the head, murrelets depend on for nesting. assigned Threatened status by the Com- back and wings are dark brown, while Fragmented old-growth stands and mittee on the Status of Endangered the throat, chest and abdomen are isolated patches are believed to provide Wildlife in Canada () in 1990. brown flecked with white and cinna- poor murrelet habitat because nests This national designation is applied to mon, giving a mottled or “marbled” in them are vulnerable to predators any species “that is likely to become appearance. The winter plumage is black like ravens, and to wind and other dis- endangered in Canada if the factors above and white below. Males and turbances. affecting its vulnerability do not females have similar colouring. In British In recent years, oil spills and drown- become reversed.” This status was Columbia, the only other seabird of ing in gill nets set for salmon have based on loss of nesting habitat and on similar size and shape is the Ancient caused some murrelet deaths on the additional threats posed by oil spills Murrelet. In summer this species is British Columbia coast. Although large and fishing nets. The Marbled Murrelet black and white and not likely to be numbers of birds were not involved, is on British Columbia’s Red List of confused with its marbled relative. even low levels of human-caused species being considered for legal des- In winter, when both are black and mortality are of concern for a species ignation as Endangered or Threatened. white, the Marbled Murrelet can be like the murrelet that produces only The combined Washington-Oregon- distinguished by its white throat and one young each year. A major oil spill California population was listed as a horizontal white strip above the could be catastrophic. federally Threatened by the United folded wing. Human activities are undoubtedly States Fish and Wildlife Service in 1992. When airborne, the stubby wings having an adverse impact on the Individual states have also applied their of the murrelet beat very rapidly, What makes them unique? he mysterious Marbled Murrelet has fascinated ornithologists for decades. Tantalising clues to its nesting habits, Tsuch as the discovery of fledglings or eggshell fragments on the forest floor miles from the sea, accumulated for years without anyone finding an actual nest. This meagre evidence suggested that despite being marvellously adapted for life at sea, this species nested far inland in ancient forests. Recent nest discoveries have confirmed this rather radical departure from the habits of other seabirds. But some puzzles remain. Why would a bird that must carry fish to its chick at dawn and dusk, nest 60 or more kilometres inland, when apparently suit- able sites occur closer to the sea? Whatever the explanation, such behav- iour must be beneficial. All the other members of the auk family nest in burrows in dense colonies on small offshore islands and are adapted for this lifestyle. The Marbled Murrelet’s brown breeding season plumage and greenish-tinted egg, both unusual among alcids, appear to be adaptations for nesting in the forest. This cryptic colouring provides camouflage and reduces the risk of being spotted by predators. and its zigzag flight over the bled Murrelet However, forest fragmentation can water has prompted some is a high- open the forest to new predators that observers to liken it to “an over- The bulk of pitched “keer- are more adept at detecting murrelets sized bumblebee.”Murrelets have the murrelet keer,” used for and their eggs. small feet, webbed like those of a communica- This species differs from most for- duck, that they use to paddle on population tion between est-nesting birds in that it does not nest the water surface. When diving, nests in forests individuals in cavities or build a nest among they essentially “fly” underwater, and most often branches. Most murrelets nest on a using their muscular wings as having little heard around thick, mossy platform on a thick limb flippers and their feet only for protection from dawn or dusk or on some kind of broad deformity on steering. They demonstrate great as the birds fly a trunk. Only old trees provide these speed and agility during bouts of future logging. to and from types of sites, which greatly limits the underwater fishing. Murrelets their nests. The murrelet’s choices of places to nest. are well adapted for life in cold “keer” call is Due to its dependence on old- north-Pacific waters. Their dense used to determine the relative abun- growth trees for nesting, at least from waterproof feathers provide excellent dance and probable nesting sites of British Columbia southward, the insulation. murrelets in forested valleys during the Marbled Murrelet has become a focal The characteristic call of the Mar- nesting season. point in the conflict between logging and old-growth preservation. Once safely at sea, juveniles This has resulted in it becoming usually join other murrelets, the subject of much research but must forage for them- activity by biologists and natu- selves. They probably do not ralists, and brought it to the breed until at least two or attention of foresters, loggers three years of age. and the general public. Nat- Most natural mortality uralists, particularly from inland results from predation on areas, now place this bird high eggs and nestlings, and from on their list of sought-after loss of fledglings that do not species. make it to the sea. Like other birds with a low reproductive Range of the Marbled Murrelet in How do they reproduce? North America rate, survival and longevity of he nesting habits of the Mar- individuals reaching adult- bled Murrelet, until recently hood are expected to be good. one of the great enigmas of appear to be common where the birds Marbled Murrelets are frequently T ornithology, are still poorly known. have a greater selection of nest sites. seen in pairs in all seasons, suggesting Although the species is commonly seen Only one egg is laid, but it is large that they mate for life. on coastal waters during its breeding sea- for such a small bird – about the son, only about 50 nests had been found size of a large chicken egg! The egg What do they eat? in British Columbia as of 1997. is pale greenish- arbled Murrelets feed mostly on Fewer than 10 of these were yellow or green- fish up to 8 or 9 cm in length and observed while in active use.A few Despite being ish-buff with on shrimp-like crustaceans such as ground nests have been located in marvellously brown, blue or M euphausids and mysids. In British western Alaska where trees are grey spotting. Columbia, schools of juvenile Pacific scrubby or absent, but all nests adapted for Marbled Murre- sandlance and herring are an important found from British Columbia to life at sea, lets have a lengthy source of food, particularly in spring California have been in trees.
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