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. nesting season in and summer. Other marine foods Nests may be far inland, requiring this species British Columbia. include small seaperch, rockfish, long flights to and from the sea by nests far Eggs are probably anchovy, capelin and squid. Juvenile adults as they exchange incuba- laid from early salmon are sometimes caught by murre- tion duties or bring fish to feed inland in May to late June lets in lakes near the coast. The sand- their chick. ancient and most nestlings lance appears to be the fish most often The murrelet nest is very are raised from carried to nestlings. simple – a shallow, mossy forests. early June to late Marbled Murrelets normally feed depression on a large, horizon- July. A few pairs in nearshore marine waters, includ- tal tree limb, usually near the trunk. may not finish nesting until September. ing shallow bays, channels and fjords. No nesting materials are added. So Incubation, shared by both adults, is esti- Although groups of up to 100 mur- far, nests found in British Columbia mated to take 30 days. The nestling relets may be attracted to sites where have been in Sitka spruce, yellow period of about 28 days is long com- fish are concentrated by tidal currents, cedar, Douglas-fir, western hemlock pared to that of other alcids. However, they feed as individuals. Fish and and mountain hemlock trees judged young Marbled Murrelets must be crustaceans are caught by underwater to be 300 to 800 years old or older. fully developed and capable of sus- pursuit, for which the murrelet’s tor- Nest trees were at elevations of 170 to tained flight before they leave the nest. pedo-shaped body and flipper-like 1100 metres above sea level and dis- Their first flight must take them wings are well suited. Most dives for tances of 10 to 17 km from the ocean. directly to sea or, occasionally, to a food last less than 30 seconds and The nests were 17 to 42 m above the lake along their route. Juveniles are most fish, other than those carried to ground. Re-use of nests or nest trees sometimes found on the forest floor, the nest, are swallowed underwater. A may occur in remnant habitat where where they are likely to perish since frequent feeding method is to drive a options are limited, but does not they cannot readily take off from land. school of fish to the surface and hold it there with repeated shallow dives. Gwaii. Records of nestlings found During these dives the fish are on the forest floor and observa- picked off one at a time. The “boil- tions of adults flying up valleys ing” action of these fish on the sea and into the forest canopy, indi- surface often attracts other sea- cate that most coastal watersheds birds, particularly gulls which are are used for nesting. Exceptions unable to dive for their food. include heavily logged areas like At a nest near Sechelt, British the southeast coast of Vancouver Columbia, investigators reported Island. that the chick was fed by both Marbled Murrelets may also parents beginning shortly after been seen on coastal lakes, main- 5 a.m. each day. Adults usually ly in summer, but occasionally in arrived alone, with one 7 to 8-cm winter. Most lakes where they sandlance held crossways in the have been observed are within bill. Fish were always offered to 20 km of the sea, but some, like the young murrelet headfirst, Cultus and Harrison lakes, are after which the adult made a - . up to 75 km inland. The pre- Mark Hobson photo hasty departure. Sometimes both ferred lakes are rearing areas for parents arrived at the same time juvenile salmon. and one had to wait its turn to feed both food and nesting habitat. the nestling. On many days the chick Important foraging sites include tidal What can we do? received seven fish – five in the morn- rips through narrow passages, shelves he plight of the Marbled Murrelet is ing and two in the evening. at the mouths of inlets, and shallow now widely recognised and the banks. Large feeding concentrations species has been legally designated as Where do they live? have been reported at Sechelt Inlet, T Threatened or Endangered in all he Marbled Murrelet is the most Cortes Island, Flores Island, Barkley jurisdictions south of Alaska. A 1993 widely distributed alcid in British Sound, Clayoquot Sound and off the Recovery Plan prepared by the Marbled Columbia. In summer it is common West Coast Trail. Murrelet Recovery Team describes the T along the entire coast. In winter it Marbled Murrelets are believed to programs and funding needed to protect occurs sparsely along the north coast, nest along the entire British Columbia Marbled Murrelets in Canada “... by but is relatively abundant in sheltered coast, usually within 20 km of saltwa- reducing threats to their nesting habitat waters to the south, particularly in ter, but possibly much further inland, and reducing risks faced by birds at sea.” Georgia Strait and adjacent fjords. as happens elsewhere in their range. But plans on their own do not save Some birds probably move south of Nesting occurs on large coastal islands; wildlife. Strong public support is needed, British Columbia in winter. In spring, whether small forested islands are also particularly to save suitable old-growth an influx of murrelets has been noted at used is not known. Most nesting is in nesting habitat in British Columbia. several coastal locations, from early the Coastal Western Hemlock zone, but Murrelets probably nest in most April to early May. a nest was recently discovered in the large, unlogged areas along the British In contrast to most alcids, Mar- subalpine Mountain Hemlock bled Murrelets prefer waters within 2 zone. Although it is possible, par- km of land and are often found in ticularly in northern British Col- channels and fjords along the inner umbia, that murrelets might nest coast. They also frequent exposed on the ground in alpine or sub- coastlines like the west coast of Van- alpine habitats, there is no evidence couver Island, but there too, are usu- of this at present. In British Col- ally close to shore. Though wide- umbia, nests have been found in the spread, this species has a clumped forests of Desolation and Clayoquot distribution pattern that is deter- sounds, the Carmanah-Walbran mined during all seasons by the avail- area of southwest Vancouver Island, ability of food, and in summer by the Sechelt Peninsula and Haida . Mark Hobson photo . . BCCF Marbled Murrelet Project, Tom Ainsworth photo SFU Marbled Murrelet Research Project, John Kelson photo
undoubtedly protect some critical murrelets in coastal waters is required nesting habitat. for mapping of regional sensitivity to More field studies and detailed sur- oil spills. Although significant mortali- veys are still required to determine how ty of murrelets due to drowning in gill to integrate the needs of this species with nets may be rare and localised, contin- those of other wildlife. This will allow ued monitoring is needed to ensure the resource managers to establish unhar- problem is properly controlled. British vested forest networks that will accom- Columbia should be encouraged to modate spawning salmon, Grizzly maintain the current ban on the use of Bears, Roosevelt Elk, Spotted Owls, monofilament nets, as these are known Northern Goshawks and other wildlife, to kill seabirds. as well as Marbled Murrelets. Interested naturalists can provide Conservation agencies and the pub- invaluable assistance by reporting any lic must also remain alert to the threat nests, or evidence of nesting, to the of oil spills and ensure that shipping nearest BC Wildlife Branch office. The regulations and clean-up capabilities public is urged to become more famil- are sufficient to prevent serious mor- iar with this threatened seabird and to tality of murrelets and other marine support the research, inventory and species. Improved inventory of the sea- habitat protection programs needed . SFU Marbled Murrelet Research Project, sonal distribution and abundance of to save it. Ross Vennessland photo Columbia coast. Key nesting habitats must be located, described and , : mapped so they can be protected. Wildlife Branch A landscape-level approach to habi- Ministry of Environment, Lands and Parks tat conservation is clearly required. PO Box 9374, Stn Prov Govt A start has been made, with several co- Victoria, British Columbia V8W 9M4 operative inland and at-sea surveys involving provincial and federal wildlife agencies, the BC Minis-try of Forests, Forest Renewal British Columbia logging companies, universities and conservation groups. The Identified --- . Wildlife Management Strategy, Biodi- . versity Guidelines and other habitat , conservation measures being developed under the Forest Practices Code will Printed in British Columbia on recycled paper with vegetable inks ..