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We recorded the population size and nest tree use of Red-breasted Sapsuckers (Sphyrapicus ruber) breeding in coastal, old-growth, temperate rainforest on East Limestone Island. Haida Gwaii. British Columbia, over 31 years (1990-2020). The populations density on the 48 ha island ranged from 10 to 46 occupied nests/[km.sup.2], with numbers increasing and then decreasing from 1991 to 2005, followed by a gradual increase between 2006 and 2020. The population size was unaffected by a major windthrow event in 2010 that destroyed about a third of the preferred forest type. Nor did breeding birds avoid the remaining trees left within the blowdown area, suggesting that the retention of isolated dead trees within small forest openings may provide useful breeding sites for sapsuckers. Individual trees were used up to 10 times and continued to be selected for up to 21 years after first use, with use being more prolonged for Sitka spruce (Picea sitchensis) than for western hemlock (Tsuga heterophylla). Maximum span of use probably exceeds 23 years. There was a significant tendency for trees to be used in consecutive years. Modeling the availability of trees used at least once suggested that in all years there were ample suitable trees available, and hence that the population was not constrained by lack of suitable nest sites. Received 5 January 2022. Accepted 3 January 2023. Key words: cavity-nesting, coastal temperate rainforest, Haida Gwaii, nest tree use, Sitka spruce, western hemlock. Nous avons enregistre la taille de la population et l'utilisation des arbres de nidification des Pics a Poitrine Rousse (Sphyrapicus ruber) qui nichent dans la foret pluviale temperee cotiere et aneienne de l'ile East Limestone, a Haida Gwaii. en Colombie-Britannique. La densite des populations sur cette ile de 48 ha variait de 10 a 46 nids occupes/[km.sup.2]. avec une augmentation puis une diminution des effectifs de 1991 a 2005, suivie d'une augmentation progressive entre 2006 et 2020. La taille de la population n'a pas etc affectee a la suite d'un chablis majeur qui. en 2010. a delruit environ un tiers du type de foret prefere par l'espece. Les oiseaux nichcurs ont continue a utiliser les arbres restants dans la zone de chablis. ce qui suggere que la retention d'arbres morts isoles dans de petites ouvertures forestiercs petit fournir des sites de reproduction utiles pour les pics. Certains de ces arbres ont ete utilises jusqu'a 10 reprises et out continue a etre selectionnes jusqu'a 21 ans apres leur premiere utilisation, l'utilisation etant plus prolongee pour l'epicea de Sitka (Picea sitchensis) que pour la pruche de l'ouest (Tsuga heterophylla). La duree maximale d'utilisation depasse probablement 23 ans. Il y avail une tendance significative chez ces arbres a etre utilises au cours d'annees consecutives. La modelisation de la disponibilite des arbres utilises au mains une fois suggere qu' il y avail chaque annee suffisamment d'arbres adequats disponibles. et done que la population n'etait pas limitee par le manque de sites de nidification appropries. Mots cles: epieea de Sitka, foret pluviale temperee cotiere. Haida Gwaii, nidification cavicole. pruehe de l'ouest. utilisation des arbres de nidification., Sapsuckers (Sphyrapicus spp.) are among the most common woodpeckers in most forested areas of British Columbia, Canada. The genus is represented in the province by 4 largely allopatric species, all [...]

Systematic transect surveys of marine birds in eastern Queen Charlotte Strait and the western part of Johnstone Strait, British Columbia, Canada, were made between mid-August and mid-October 2020-2022. All birds within 100-m transect strips were counted and numbers corrected for detectability. Extrapolating within five regions of differing ecological characteristics and seabird densities, our results indicate that the study area supported 1% or more of the North American populations of Pigeon Guillemot Cepphus columba, Marbled Murrelet Brachyramphus marmoratus, California Gull Larus californicus, Glaucous-winged Gull L. glaucescens, Iceland Gull L. glaucoides, and Short-billed Gull L. brachyrhynchos. Our estimation of gull species in our study area would have been even higher if gulls in flight had been included in our survey. Furthermore, maximum estimates of Common Murre Uria aalge exceed the total population breeding in British Columbia. Only Pigeon Guillemot, Marbled Murrelet, and Glaucous-winged Gull breed in Queen Charlotte Strait, and only Marbled Murrelet is considered to be "at risk." However, based on current criteria, it seems that the area would be a prime candidate for nomination as an International Union for Conservation of Nature (IUCN) Key Biodiversity Area. [ABSTRACT FROM AUTHOR]

The Marbled Murrelet Brachyramphus marmoratus breeds and overwinters along the coast of British Columbia, Canada, and is listed as Threatened under the Canadian Species at Risk Act. Understanding population trends for this seabird species is important for management and recovery, yet long-term time-series data for Marbled Murrelet abundance are rare. We update trends and annual fluctuations of Marbled Murrelet numbers derived from at-sea counts in Laskeek Bay, Haida Gwaii, on the north coast of British Columbia, 1990-2020. We found a non-significant negative trend (-1.55% per year). Counts varied seasonally and peaked in early June; counts also varied with distance from shore, with the highest numbers occurring within 1 km of shore. Importantly, a change in survey protocol after 1996, which reduced the transect width from 400 m to 100 m, resulted in lower counts, and we found that counts were 2.7 times greater when wider transects were surveyed. Inter-annual fluctuations in counts were high, but we found no significant relationships between bird counts and either large-scale oceanographic cycles or more localized indicators of ocean productivity. Compared to previous analyses of this dataset, which showed strong declines, the absence of a trend in at-sea counts is more in line with trends derived from systematic radar counts conducted within the Haida Gwaii conservation region over a similar period (-2.8% per year). Our study emphasizes the need to investigate fluctuations in at-sea counts more closely to understand what may be driving peaks in at-sea counts, including possible movement of birds between regions. [ABSTRACT FROM AUTHOR]