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Delineating habitat requirements and preferences of species is essential for conservation planning. We studied nest habitat use and effects of microsite vegetation characteristics on breeding success of yellow-rumped warblers ( Dendroica coronata (L., 1766)), blackpoll warblers ( Dendroica striata (J.R. Forster, 1772)), and white-throated sparrows ( Zonotrichia albicollis (Gmelin, 1789)) in an area with a low extent (<6% of available land) of forest harvest in northwestern Newfoundland. During 2004 and 2005, 99 nests were located and monitored, and the characteristics of nest sites measured. Vegetation at yellow-rumped and blackpoll warbler nest sites differed from random sites; however, within used sites, no vegetation characteristics were significantly associated with success. White-throated sparrow nest sites contained more downed wood and less ground vegetation than did random sites; however, successful nests were associated with different variables than those that distinguished them from random sites, including less canopy cover and less woody debris. Thus, whereas yellow-rumped and blackpoll warblers used specific nest-site characteristics and white-throated sparrows had higher nest success associated with certain characteristics, the nest characteristics these birds appeared to choose did not have demonstrable fitness benefits.

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Fish exhibit habitat‐specific distributions in heterogeneous landscapes. Many sampling techniques are limited to specific seabed types and have limited utility in comparisons of fish abundance among multiple habitats. We measured the relative abundance and the composition of fish communities in four naturally occurring coastal marine seabed types (sand–pebble, cobble, bedrock, and eelgrass) and one anthropogenic habitat type (wharf) in Newman Sound, Newfoundland, Canada, by using baited video cameras. Fish and macroinvertebrate communities were significantly different among habitat types. Winter Flounder Pseudopleuronectes americanus, Atlantic Cod Gadus morhua, and Shorthorn Sculpin Myoxocephalus scorpius were significantly more abundant over sand–pebble substrate compared with bedrock and wharf sites. Cunners Tautogolabrus adspersus and Greenland Cod Gadus macrocephalus ogac were most abundant at wharf sites. Atlantic rock crabs Cancer irroratus and American lobsters Homarus americanus avoided sand–pebble seabeds, and American lobsters were almost exclusive to bedrock sites. Cunners, Winter Flounder, and Atlantic Cod were more abundant in summer, whereas Greenland Cod and Atlantic rock crabs were more abundant during autumn months. In paired comparisons of eelgrass habitats, the community sampled by two methods was different. Relative abundance estimates from baited video cameras matched beach seine estimates for abundant predatory species (e.g., Cunner, Greenland Cod, and Atlantic rock crab), but other species, including age‐0 Greenland Cod, Shorthorn Sculpin, and White Hake Urophycis tenuis, were better represented in beach seine samples. We demonstrated substrate preferences by common coastal marine fish and crab species, which have proven difficult to enumerate via active sampling techniques in the past. Our findings will facilitate comparative studies for these species among habitat components. For species that are well sampled by using baited video cameras, this technique will advance our ability to plan for their management in the nearshore.

Newfoundland’s Banded Killifish (Fundulus diaphanus) population is listed as a species of Special Concern under Canada’s Species at Risk Act and Vulnerable under Newfoundland and Labrador’s Endangered Species Act. Mummichog (Fundulus heteroclitus) is a similar looking fish species and is currently under review by Newfoundland and Labrador’s Species Status Advisory Committee. Both species have limited known distributions in Newfoundland waters that overlap. They may occur sympatrically in estuaries and occasionally hybridize; thus, field identifications can be challenging. We found that dorsal fin position and caudal fin depth were the most useful morphological characters for distinguishing Banded Killifish and Mummichog in the field. We used local ecological knowledge, literature review, museum records, and field surveys to update the known distribution ranges and found both species in more locations than previously documented in Newfoundland. Thus, we extend their known ranges. Our results will be critical in future status assessments of these species in Newfoundland.