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At least 37 records · Page 2Linked to original sources
USGS2000

Mechanisms of population differentiation in marbled murrelets: historical versus contemporary processes

Mechanisms of population differentiation in highly vagile species such as seabirds are poorly understood. Previous studies of marbled murrelets ( Brachyramphus marmoratus ; Charadriiformes: Alcidae) found significant population genetic structure, but could not determine whether this structure is due to historical vicariance (e.g., due to Pleistocene glaciers), isolation by distance, drift or selection in peripheral populations, or nesting habitat selection. To discriminate among these possibilities, we analyzed sequence variation in nine nuclear introns from 120 marbled murrelets sampled from British Columbia to the western Aleutian Islands. Mismatch distributions indicated that murrelets underwent at least one population expansion during the Pleistocene and probably are not in genetic equilibrium. Maximum-likelihood analysis of allele frequencies suggested that murrelets from 'mainland' sites (from the Alaskan Peninsula east) are genetically different from those in the Aleutians and that these two lineages diverged prior to the last glaciation. Analyses of molecular variance, as well as estimates of gene flow derived using coalescent theory, indicate that population genetic structure is best explained by peripheral isolation of murrelets in the Aleutian Islands, rather than by selection associated with different nesting habitats. No isolation-by-distance effects could be detected. Our results are consistent with a rapid expansion of murrelets from a single refugium during the early-mid Pleistocene, subsequent isolation and divergence in two or more refugia during the final Pleistocene glacial advance, and secondary contact following retreat of the ice sheets. Population genetic structure now appears to be maintained by distance effects combined with small populations and a highly fragmented habitat in the Aleutian Islands.

Evolution↗
USGS2003

Radio-telemetry evidence of re-nesting in the same season by the Marbled Murrelet

Unlike other alcids, laying of replacement eggs has not been well documented in Brachyramphus murrelets. Observations of two radio-marked Marbled Murrelets ( Brachyramphus marmoratus ) in northern California during 2001 and 2002 suggested that they can re-lay in the same breeding season. In 2001, aircraft telemetry first detected a male Marbled Murrelet at a forested inland location on 17 May. This bird alternated 24h incubation bouts with 24h at sea periods until 29 May, when data logger recordings indicated that the bird arrived at the nest at 05.17 h (PDT), but left at 05.32 h. This nesting effort had apparently failed. Sixteen days later, on 14 June this murrelet arrived in the vicinity of the first nest site at 05.19 h and remained there until 18.57 h that same evening and then left. We suspected that this event represented a second breeding effort that also failed, either near or at the site of the first effort. In 2002 a female Marbled Murrelet, first detected inland on 13 June by aircraft telemetry, alternated on the nest one day and at sea the next until 23 June when the breeding effort is presumed to have failed. This bird was again detected inland on 21 July, and alternated on the nest one day and at sea the following day until 3 August, when the radio-transmitter fell off the bird. Video recordings at the nest site indicated this second nesting attempt continued until 1 September, when the chick died of unknown causes. As in other alcids, re-laying apparently occurred 2-4 weeks after failure of the first eggs, either near or at the site of first eggs. Re-nesting may be frequent in murrelets, given the high rates of breeding failure reported.

California↗
USGS1993

Distribution and abundance of Marbled Murrelets in Alaska

Most seabirds breed in colonies on offshore islands, but throughout most of their range from California to Alaska Marbled Murrelets ( Brachyramphus marmoratus ) fly inland to nest on trees in old-growth coniferous forests. Some fraction of the murrelet population nests on the ground in Alaska. The relative distribution and abundance of murrelets in forested and treeless areas of Alaska is poorly known. We analyzed data on seabird abundance at sea and on colonies in Alaska that were obtained under the Outer Continental Shelf Environmental Assessment Program during the 1970s and 1980s. Whereas most seabirds may be censused at breeding colonies, murrelet populations must be estimated from surveys at sea. We compared colony and pelagic population estimates for 13 colonial seabird species in Alaska and found that they were strongly correlated (r 2 = 0.94). We therefore used at-sea censuses to estimate that at least 160,000 murrelets reside in Alaska. Most (97%) Marbled Murrelets are concentrated offshore of large tracts of coastal coniferous forests in southeast Alaska (Alexander Archipelago), Prince William Sound, and the Kodiak Archipelago.

Alaska↗
USGS2000

Temporal variability in abundance of Marbled Murrelets at sea in southeast Alaska

We examined effects of season, time of day, tide stage, tidal oscillation, and sea surface temperature on Marbled Murrelet ( Brachyramphus marmoratus ) abundance and distribution at sea. We also evaluated whether constraining surveys to specific time periods or tide stages would reduce temporal variability in counts. Murrelets were surveyed daily from small boats and from shore in Auke Bay and Fritz Cove, Alaska, from May through August in 1992 and 1993. Murrelet numbers were high before egg-laying, declined by more than half during egg-laying and incubation and were highly variable during chick-rearing and fledging. Murrelet numbers were highest in early and late morning and declined throughout the day, sometimes increasing slightly in the evening. Peak murrelet numbers occurred on high or falling morning tides, especially in shallow areas where Pacific sand lance ( Ammodytes hexapterus ) were abundant. Differences between years in murrelet abundance and breeding phenology probably resulted from interannual differences in the pattern of seasonal warming and subsequent effects on production at lower trophic levels. We recommend that surveys for trends in abundance in Southeast Alaska be conducted in early morning, in June, at high or falling tides. Power analyses indicated that surveys conducted in this manner would minimize the number of years required to detect a significant change in abundance.

Alaska↗
USGS1998

Marbled murrelets have declined in Alaska

In the last issue of Northwest Science , Hayward and Iverson (“Long-Term Trends in Marbled Murrelets in Southeast Alaska Based on Christmas Bird Counts”) failed to mention other evidence for 40-75% declines in murrelet populations, or discuss implications of a climate regime shift that has reduced populations of seabirds in Alaska, or present any useful information on the status of old-growth breeding habitat for murrelets. They examined Christmas Bird Count (CBC) data from Southeast Alaska, and concluded that there is no evidence for declines in populations. They suggested that our (Piatt and Naslund 1995) previous analysis of CBC data for murrelets was erroneous, and suggested that “ the disparity between our conclusions… invites explanation ”. Invitation accepted. In the following, I will show that there was no disparity in conclusions, that Hayward and Iverson mis-represented our conclusions and they conducted a highly selective review of evidence for murrelet population changes in Alaska. The result was a paper that was inaccurate, incomplete, out-of-date, mis-leading and of little service to the readers of Northwest Science who might have read the article hoping to gain some new insight on the status of marbled murrelets in Alaska.

Alaska↗
USGS2019

Monitoring and conservation of Japanese Murrelets and related seabirds in Japan

Of the 24 species in the Auk (or Alcidae) family of seabirds living in the northern hemisphere, 22 reside within the North Pacific Ocean. These “penguins of the north” use their small wings to “fly” underwater, some to more than 200 meters, where they catch and eat a variety of small fish and invertebrates. In terms of sheer numbers (>65 million) and food consumption, the Auks dominate seabird communities on our continental shelves and they serve as indicators of the health of our ocean. If Auk populations are not all thriving, then we should be concerned about the status of the oceans, plankton and fish that normally sustain them. A few Auk “tribes” genera) are abundant and widespread (such as Uria murres and Aethia auklets), and some are rare and isolated such as Synthliboramphus murrelets, including the Japanese “Crested” Murrelet). Only 8 species of Auk breed in Japan, including species that have either widespread or isolated populations in the North Pacific. During the past century, most of these Auks have declined dramatically in Japan from many causes, including the introduction of predatory rats and cats to breeding islands, bycatch in fishing nets, alteration of food supplies by fishing and climate change, oil spills, and destruction of seabird nesting habitats. Widespread species such as the Common Murre and Tufted Puffin were once common in Japan but now breed in low numbers at only a few locations. Probably common in the past, small numbers of the widespread Ancient Murrelet were recently re-discovered breeding at Teuri Island, which is also home to the world’s largest colony of Rhinoceros Auklet, another widespread species. Though common throughout the North Pacific, Pigeon Guillemots, breed only in the southern Kuril Islands. Their population status is unknown, but they were never considered common in Japan. In contrast, Spectacled Guillemots are an example of an uncommon and isolated population of Auk. They nest along coasts of the Sea of Okhotsk and Sea of Japan, and populations have declined in recent decades. The Long-billed Murrelet has a similar distribution to Spectacled Guillemot, and once bred in Hokkaido, but populations appear to have been extirpated. The Japanese Murrelet has a very small world population, and breeds at only a few locations in southern Japan and the Republic of Korea. The international community of research and conservation biologists is greatly concerned about the ability of this species—probably the rarest of all Auks in the world— to maintain its population size. Owing to its small size and high metabolic demand, this species is especially vulnerable to any stress that increases its food requirements such as changing fish stocks, disturbance on feeding or wintering grounds, or changing ocean climate. Immediate management actions are needed to preserve Japanese Murrelets and other Auks in Japan, by such means as eradicating rats and cats on breeding islands, altering fishing gear to minimize bycatch, and reducing human disturbance to nesting habitats. More research and monitoring of Auk populations in Japan is needed to track population trends, and further identify factors responsible for declines. Interaction between governments and biologists at regional and international levels will be mutually beneficial as we all strive to conserve precious resources and biodiversity in the northwest Pacific, and particularly the Japanese islands.

Conference Paper↗
USGS2014

Modeling marbled murrelet (Brachyramphus marmoratus) habitat using LiDAR-derived canopy data

LiDAR (Light Detection And Ranging) is an emerging remote-sensing tool that can provide fine-scale data describing vertical complexity of vegetation relevant to species that are responsive to forest structure. We used LiDAR data to estimate occupancy probability for the federally threatened marbled murrelet ( Brachyramphus marmoratus ) in the Oregon Coast Range of the United States. Our goal was to address the need identified in the Recovery Plan for a more accurate estimate of the availability of nesting habitat by developing occupancy maps based on refined measures of nest-strand structure. We used murrelet occupancy data collected by the Bureau of Land Management Coos Bay District, and canopy metrics calculated from discrete return airborne LiDAR data, to fit a logistic regression model predicting the probability of occupancy. Our final model for stand-level occupancy included distance to coast, and 5 LiDAR-derived variables describing canopy structure. With an area under the curve value (AUC) of 0.74, this model had acceptable discrimination and fair agreement (Cohen's κ = 0.24), especially considering that all sites in our sample were regarded by managers as potential habitat. The LiDAR model provided better discrimination between occupied and unoccupied sites than did a model using variables derived from Gradient Nearest Neighbor maps that were previously reported as important predictors of murrelet occupancy (AUC = 0.64, κ = 0.12). We also evaluated LiDAR metrics at 11 known murrelet nest sites. Two LiDAR-derived variables accurately discriminated nest sites from random sites (average AUC = 0.91). LiDAR provided a means of quantifying 3-dimensional canopy structure with variables that are ecologically relevant to murrelet nesting habitat, and have not been as accurately quantified by other mensuration methods.

Oregon↗
USGS2022

Kittlitz’s murrelet seasonal distribution and post-breeding migration from the Gulf of Alaska to the Arctic Ocean

Kittlitz’s Murrelets ( Brachyramphus brevirostris ) nest during summer in glaciated or recently deglaciated (post-Wisconsin) landscapes. They forage in adjacent marine waters, especially those influenced by glacial meltwater. Little is known of their movements and distribution outside the breeding season. To identify post-breeding migrations of murrelets, we attached satellite transmitters to birds (n = 47) captured at sea in the Gulf of Alaska and Aleutian Islands during May – July 2009 – 15 and tracked 27 birds that migrated from capture areas. Post-breeding murrelets migrated toward the Bering Sea, with short periods of movement (median 2 d) separated by short stopovers (median 1 d). Travel speeds averaged 79.4 km d-1 (83.5 SD, 449.1 maximum). Five Kittlitz’s Murrelets tagged in Prince William Sound in May migrated to the Bering Sea by August and four continued north to the Arctic Ocean, logging 2500 – 4000 km of travel. Many birds spent 2‒3 weeks with little movement along coasts of the Alaska Peninsula or eastern Bering Sea during late August through September, also the pre-basic molt period. Ship-based surveys, many of which were conducted concurrently with our telemetry studies, confirmed that substantial numbers of Kittlitz’s Murrelets migrate into the Arctic Ocean during autumn. They also revealed that some birds spend winter and spring in the Bering Sea in association with ice-edge, polynya, or marginal ice zone habitats before returning to summer breeding grounds. We conclude that this species is best characterized as a sub-Arctic and Arctic species, which has implications for future risk assessments and threat mitigation.

Alaska↗
USGS2009

Meeting reproductive demands in a dynamic upwelling system: Foraging strategies of a pursuit-diving seabird, the marbled murrelet

Seabirds maintain plasticity in their foraging behavior to cope with energy demands and foraging constraints that vary over the reproductive cycle, but behavioral studies comparing breeding and nonbreeding individuals are rare. Here we characterize how Marbled Murrelets (Brachyramphus marmoratus) adjust their foraging effort in response to changes in reproductive demands in an upwelling system in central California. We radio-marked 32 murrelets of known reproductive status (9 breeders, 12 potential breeders, and 11 nonbreeders) and estimated both foraging ranges and diving rates during the breeding season. Murrelets spent more time diving during upwelling than oceanographic relaxation, increased their foraging ranges as the duration of relaxation grew longer, and reduced their foraging ranges after transitions to upwelling. When not incubating, murrelets moved in a circadian pattern, spending nighttime hours resting near flyways used to reach nesting habitat and foraging during the daytime an average of 5.7 km (SD 6.7 km) from nighttime locations. Breeders foraged close to nesting habitat once they initiated nesting and nest attendance was at a maximum, and then resumed traveling longer distances following the completion of nesting. Nonbreeders had similar nighttime and daytime distributions and tended to be located farther from inland flyways. Breeders increased the amount of time they spent diving by 71-73% when they had an active nest by increasing the number of dives rather than by increasing the frequency of anaerobiosis. Thus, to meet reproductive demands during nesting, murrelets adopted a combined strategy of reducing energy expended commuting to foraging sites and increasing aerobic dive rates. ?? 2009 by The Cooper Ornithological Society. All rights reserved.

Condor↗
USGS1999

Vocalizations of the Kittlitz's Murrelet

We present the first documentation of Kittlitz's Murrelet (Brachyramphus brevirostris) vocalizations, based on recordings made in Glacier Bay, Alaska, in 1994. We identified two apparently related types of calls: groan and quack. The Kittlitz's Murrelet calls were markedly different from the most common calls of the congeneric Marbled Murrelet (Brachyramphus marmoratus), but shared characteristics with the Marbled Murrelet's less common 'groan' call. Phylogeny, breeding biology, and habitat characteristics may explain relationships between the congeneric vocalizations. More complete knowledge of the Kittlitz's Murrelet vocal repertoire is needed before vocalizations can be either used or discarded in the design of effective programs to monitor this rare and poorly-known species.

Condor↗
USGS2018

Abundance and productivity of marbled murrelets (Brachyramphus marmoratus) off central California during the 2017 breeding season

Marbled murrelets ( Brachyramphus marmoratus ) have been listed as “Endangered” by the State of California and “Threatened” by the U.S. Fish and Wildlife Service since 1992 in California, Oregon, and Washington. Information regarding marbled murrelet abundance, distribution, population trends, and habitat associations is critical for risk assessment, effective management and evaluation of conservation efficacy, and ultimately to meet Federal- and State-mandated recovery efforts for this species. During June–August 2017, the U.S. Geological Survey Western Ecological Research Center continued previously established, long-term (1999–2016), at-sea surveys to estimate abundance and productivity of marbled murrelets in U.S. Fish and Wildlife Service Conservation Zone 6 (central California—San Francisco Bay to Monterey Bay). Using conventional distance sampling methods, we estimated marbled murrelet abundance using 189 detections of 321 individuals observed on nine unique surveys. The abundance estimated for the entire study area using all surveys in 2017 was 530 birds (95-percent confidence interval, 384–732 birds). Estimated abundance from 2017 is comparable to most prior years of study, except for 2008 and 2015, which had anomalously low abundances. We estimated productivity (calculated as the hatch-year [HY] to after-hatch-year [AHY] ratio) in 2017 using three detections of three individuals observed in six surveys. After date-correcting HY and AHY counts to account for birds expected to be absent from the water while inland at nests, the date-corrected juvenile ratio was 0.022 ± 0.014 standard error. We created a synthesized database of all marbled murrelet survey data from 1999 to 2017 to allow scientists and managers to evaluate established survey methods and assess trends in abundance and productivity estimates. Future modifications of survey design could help reduce variance in abundance estimation.

California↗
USGS2019

Abundance and productivity of marbled murrelets (Brachyramphus marmoratus) off central California during the 2018 breeding season

Executive Summary Marbled murrelets ( Brachyramphus marmoratus ) have been listed as “endangered” by the State of California and “threatened” by the U.S. Fish and Wildlife Service since 1992 in California, Oregon, and Washington. Information regarding marbled murrelet abundance, distribution, population trends, and habitat associations is critical for risk assessment, effective management, evaluation of conservation efficacy, and ultimately, to meet Federal- and State-mandated recovery efforts for this species. During June–August 2018, the U.S. Geological Survey Western Ecological Research Center continued previously established, long-term (1999–2018), at-sea surveys to estimate abundance and productivity of marbled murrelets in U.S. Fish and Wildlife Service Conservation Zone 6 (San Francisco Bay to Point Sur in central California). Using conventional distance sampling methods, we estimated marbled murrelet abundance using 137 detections of 227 individuals observed on 9 surveys. The abundance estimated for the entire study area using all surveys in 2018 was 370 birds (95-percent confidence interval, 250–546 birds). Estimated abundance from 2018 is comparable to most prior years of study, except for 2001–03, when greater abundances were estimated. In 2018, we estimated reproductive productivity (calculated as the hatch-year [HY] to after-hatch-year [AHY] ratio) using four detections of four HY individuals observed on six surveys. After date-correcting HY and AHY counts to account for birds expected to be absent from the water while inland at nests, the date-corrected juvenile ratio was 0.047 ± 0.024 standard error. We updated a synthesized database of all Zone 6 marbled murrelet survey data since 1999 with 2018 data to allow scientists and managers to evaluate established survey methods and assess trends in abundance and productivity estimates.

California↗
USGS2001

Using resampling to assess reliability of audio-visual survey strategies for marbled murrelets at inland forest sites

Marbled Murrelets (Brachyramphus marmoratus) are threatened seabirds that nest in coastal old-growth coniferous forests throughout much of their breeding range. Currently, observer-based audio-visual surveys are conducted at inland forest sites during the breeding season primarily to determine nesting distribution and breeding status and are being used to estimate temporal or spatial trends in murrelet detections. Our goal was to assess the feasibility of using audio-visual survey data for such monitoring. We used an intensive field-based survey effort to record daily murrelet detections at seven survey stations in the Oregon Coast Range. We then used computer-aided resampling techniques to assess the effectiveness of twelve survey strategies with varying scheduling and a sampling intensity of 4-14 surveys per breeding season to estimate known means and SDs of murrelet detections. Most survey strategies we tested failed to provide estimates of detection means and SDs that were within A?20% of actual means and SDs. Estimates of daily detections were, however, frequently estimated to within A?50% of field data with sampling efforts of 14 days/breeding season. Additional resampling analyses with statistically generated detection data indicated that the temporal variability in detection data had a great effect on the reliability of the mean and SD estimates calculated from the twelve survey strategies, while the value of the mean had little effect. Effectiveness at estimating multi-year trends in detection data was similarly poor, indicating that audio-visual surveys might be reliably used to estimate annual declines in murrelet detections of the order of 50% per year.

Waterbirds↗
USGS2018

Mercury concentrations in multiple tissues of Kittlitz's murrelets (Brachyramphus brevirostris)

Mercury (Hg) is a non-essential, toxic metal that is distributed worldwide. Mercury biomagnifies in food webs and can threaten the health of top predators such as seabirds. The Kittlitz's murrelet (Brachyramphus brevirostris) is a seabird endemic to Alaska and the Russian Far East and is a species of conservation concern in the region. We determined Hg concentrations in eggshells, guano, blood, and feathers of Kittlitz's murrelets sampled from four locations in Alaska. Mercury concentrations in eggshells, guano, and blood were low compared to other seabird species. Mean Hg concentrations of breast feathers from Adak Island and Glacier Bay were significantly greater than those from Agattu Island or Icy Bay. Two Kittlitz's murrelets at Glacier Bay and one Kittlitz's murrelet at Adak Island had Hg concentrations above those associated with impaired reproduction in other bird species, and may merit further investigation as a potential threat to individuals and populations.

Alaska↗
USGS1983

Nest sites and eggs of Kittlitz's and Marbled murrelets

Fourteen known and three probable nests of Kittlitz's Murrelet (Brachyramphus brevirostris) and eight known and one probable nest of Marbled Murrelet (B. marmoratus) have been reported. Nests of Kittlitz's Murrelet tend to be at higher elevations and farther inland than those of Marbled Murrelet. Kittlitz's nests have much less vegetative cover than Marbled nests. Nests of both species are generally a short distance below a peak or ridge, Kittlitz's on the ground and Marbled either in a tree or on the ground. The eggs of the two species are similar in color and their mean dimensions are not separable statistically. Our findings support the idea that Kittlitz's fledglings commonly get to the sea by way of streams.

Condor↗
USGS1998

Selection of forage-fish schools by Murrelets and Tufted Puffins in Prince William Sound, Alaska

We collected hydroacoustic and bird-observation data simultaneously along transects in three areas in Prince William Sound, Alaska, 21 July-11 August 1995. The probability of the association of fish schools with Marbled Murrelets ( Brachyramphus marmoratus ) and Tufted Puffins ( Fratercula cirrhata ) was determined through the use of resource selection functions based on logistic regression. Mean (± SD) group sizes were small for both species, 1.7 ± 1.1 and 1.2 ± 0.7 for Marbled Murrelets and Tufted Puffins, respectively. Oceanographically, all study areas were stratified with synchronous thermo- and pycnoclines (a water layer of increasing temperature and density, respectively, with increasing depth). Our analysis indicated that Tufted Puffins selected fish schools near their colony, whereas Marbled Murrelets selected smaller, denser fish schools in shallower habitats. We suggest that murrelets selected shallower habitats in response to lower maximum diving depths than puffins. Small feeding-groups size is discussed in terms of foraging theory and as a consequence of dispersed, low density food resources.

Alaska↗
USGS2022

Abundance and productivity of Marbled Murrelets ( Brachyramphus marmoratus ) off central California during the 2020 and 2021 breeding seasons

Marbled murrelets ( Brachyramphus marmoratus ) have been listed as “endangered” by the State of California and “threatened” by the U.S. Fish and Wildlife Service since 1992 in California, Oregon, and Washington. Information regarding marbled murrelet abundance, distribution, population trends, and habitat associations is critical for risk assessment, effective management, evaluation of conservation efficacy, and ultimately, to meet federal- and state-mandated recovery efforts for this species. During June–August 2020 and 2021, the U.S. Geological Survey Western Ecological Research Center continued previously established, long-term (1999–present), at-sea surveys to estimate abundance and productivity of marbled murrelets in U.S. Fish and Wildlife Service Conservation Zone 6 (San Francisco Bay to Point Sur in central California). The abundance estimated for the entire study area was 470 birds (95-percent confidence interval, 313–707 birds) in 2020 and 402 birds (95-percent confidence interval, 219–737 birds) in 2021. Estimated abundances for both years are comparable with most prior years of study. We estimated reproductive productivity (calculated as the hatch-year to after-hatch-year ratio) after date-correcting hatch-year and after-hatch-year counts to account for birds expected to be absent from the water while inland at nests. The date-corrected juvenile ratio was 0.018±0.011 standard error in 2020 and 0.041±0.024 standard error in 2021. We updated a comprehensive database of all Zone 6 marbled murrelet survey data since 1999 with 2020–21 data to allow scientists and managers to evaluate established survey methods and assess trends in abundance and productivity estimates.

California↗
USGS2016

Identifying Kittlitz's Murrelet nesting habitat in North America at the landscape scale

The Kittlitz's Murrelet ( Brachyramphus brevirostris ) is a small, non-colonial seabird endemic to marine waters of Alaska and eastern Russia that may have experienced significant population decline in recent decades, in part because of low reproductive success and terrestrial threats. Although recent studies have shed new light on Kittlitz's Murrelet nesting habitat in a few discrete areas, the location and extent of suitable nesting habitat throughout most of its range remains unclear. Here, we have compiled all existing nest records and locations to identify landscape-scale parameters (distance to coast, elevation, slope, and land cover) that provide potential nesting habitat in four regions: northern Alaska, Aleutian Islands, Alaska Peninsula Mountains and Kodiak Island, and Pacific Coastal Mountains (including nearshore interior Canada). We produced a final map classifying 12% (70,411 km 2 ) of the lands assessed as potential Kittlitz's Murrelet nesting habitat, with dense but distinct patches in northern Alaska and a more uninterrupted, narrow band extending across the Pacific Coastal Mountains, Alaska Peninsula Mountains, and Aleutian Islands. The extent of habitat-capable parameter values varied regionally, indicating that the Kittlitz's Murrelet may be able to use a variety of habitats for nesting, depending on availability. Future nesting habitat studies could employ spatially random sampling designs to allow for quantitatively robust modeling of nesting habitat and predictive extrapolation to areas where nests have not been located but likely exist.

Alaska↗