Faccio S.D.,Vermont Center for Ecostudies |
Amaral M.,U.S. Fish and Wildlife Service |
Amaral M.,Warner University |
Martin C.J.,Audubon Society of New Hampshire |
And 2 more authors.
Journal of Raptor Research | Year: 2013
Knowledge of dispersal patterns and survival rates is essential to understand population dynamics and demography, and to develop effective long-term management strategies for species of conservation concern. In New England, Peregrine Falcons (Falco peregrinus) were extirpated as a breeding species in the 1960s. Following a captive breeding and release program, the population subsequently underwent a rapid, dispersal-based expansion into its former range, particularly during the last two decades. Use of buildings, bridges, and other human-made structures for nesting has become widespread in urban areas, where the species only infrequently nested prior to reintroduction. We analyzed encounters of Peregrine Falcons banded as nestlings in the six New England states between May 1990 and June 2009 to determine: (a) differences in dispersal patterns (distance and direction) by sex; (b) differences in movement and natal dispersal among birds from cliff and artificial nest sites; (c) causes of mortality; and (d) effects of sex, age, and natal habitat type on survivorship. Of 986 Peregrine Falcons banded, 24% were encountered again at least once by December 2009. Although most encounters (76%) occurred within the study area, 24% were outside New England in eight other eastern states, three Canadian provinces, Cuba, and Nicaragua. Five percent of the marked population was later confirmed at breeding territories in the eastern U.S.A., primarily in New England. Females dispersed greater distances (natal dispersal = 152.6 km; range = 70.2-853.5 km; n = 28) than males (88.0 km; range = 0.03-1009.7 km; n = 22). New England peregrines showed a strong tendency to settle at nest types similar to those on which they were raised (rural cliff vs. urban structures); however, we documented movement from urban to rural habitats and vice versa in equal proportions. The causes of mortality for 122 recovered birds included unknown (61%), collisions with aircraft (11%), collisions with stationary objects (8%), falling from nest site (8%), collisions with vehicles or trains (7%), gunshot wounds (2%), entanglement in fishing gear (1%), and poisoning (1%). Most deaths occurred among first-year (68%) and second-year (11%) birds, with first-year peregrines experiencing significantly higher mortality than other age classes. The estimated annual survival rate for second-year and adult falcons combined was 81%, whereas our estimate for first-year birds was only 9%; however, the latter rate likely is a significant underestimate. We found no effect of natal habitat or sex on survival. © 2013 The Raptor Research Foundation, Inc.
Hunt P.D.,Audubon Society of New Hampshire |
Blust M.,Green Mountain College |
Morrison F.,A Natural Focus
Northeastern Naturalist | Year: 2010
Several riverine species in the insect order Odonata (dragonflies and damselflies) are recognized as being of conservation concern in the Northeast. Along the Connecticut River, most data on these species have come from the southern portion of the river that passes through Connecticut and Massachusetts, while the northern portion has been poorly sampled until recently. In this paper, we summarize recent surveys along the VermontNew Hampshire stretch of the river and place these in the context of known distributional data for the river as a whole. Our focus is on species typical of large rivers, with a particular focus on members of the family Gomphidae (clubtails). Also included is information on the first Vermont or New Hampshire records of three speciesEnallagma antennatum, Enallagma durum, and Stylurus amnicolaand the first upper river records for several other species.
Luepold S.H.B.,New York University |
Hodgman T.P.,Bird Group |
McNulty S.A.,New York University |
Cohen J.,New York University |
Foss C.R.,Audubon Society of New Hampshire
Condor | Year: 2015
Rusty Blackbird (Euphagus carolinus) populations have plummeted since the mid-20th century. Recent research in New England, USA, suggests that an ecological trap, created through timber harvesting on the breeding grounds, may be responsible. Red squirrels (Tamiasciurus hudsonicus) were hypothesized to be the primary nest predator, but definitive identification was lacking. The potential for mast cone crops to affect Rusty Blackbird nest predation via trophic interactions also remains unexamined. Our objectives were to identify the mechanisms by which an ecological trap may be operating in New England through a multiscale analysis of Rusty Blackbird habitat selection and nest survival, as well as predator identification and quantification. We located 72 Rusty Blackbird nests in Maine and New Hampshire in 2011 and 2012, and modeled habitat selection and nest survival as a function of habitat characteristics at the nest patch (5 m) and home range (500 m) scale. We placed camera traps at 29 nests to identify nest predators, and conducted ground surveys to obtain an index of squirrel abundance each year. We found that Rusty Blackbirds selected nest patches with a high basal area of small conifers and low canopy closure. Nest survival was not reduced in harvested stands, but increased with increasing basal area. Percent cover of wetlands and young softwood stands were the best predictors of Rusty Blackbird selection at the home range scale. At the home range scale, we found that nests that were closer to a road were less successful in 2011, but not in 2012. Red squirrels were the most frequent predator of Rusty Blackbird nests in 2012, when they were abundant following a mast year in 2011. These results suggest that dense cover of small softwoods is important for habitat selection and survival of Rusty Blackbird nests, and that precommercial thinning and possibly road-building could reduce habitat quality for this species. © 2015 Cooper Ornithological Society.
White E.L.,Albany State University |
Hunt P.D.,Audubon Society of New Hampshire |
Schlesinger M.D.,Albany State University |
Corser J.D.,Albany State University |
De Maynadier P.G.,50 State Street
Freshwater Science | Year: 2015
Odonata are valuable biological indicators of freshwater ecosystem integrity and climate change, and the northeastern USA (Virginia to Maine) is a hotspot of odonate diversity and a region of historical and growing threats to freshwater ecosystems. This duality highlights the urgency of developing a comprehensive conservation assessment of the region's 228 resident odonate species. We offer a prioritization framework modified from NatureServe's method for assessing conservation status ranks by assigning a single regional vulnerability metric (R-rank) reflecting each species' degree of relative extinction risk in the northeastern USA. We calculated the R-rank based on 3 rarity factors (range extent, area of occupancy, and habitat specificity), 1 threat factor (vulnerability of occupied habitats), and 1 trend factor (relative change in range size). We combine this R-rank with the degree of endemicity (% of the species' USA and Canadian range that falls within the region) as a proxy for regional responsibility, thereby deriving a list of species of combined vulnerability and regional management responsibility. Overall, 18% of the region's odonate fauna is imperiled (R1 and R2), and peatlands, low-gradient streams and seeps, high-gradient headwaters, and larger rivers that harbor a disproportionate number of these species should be considered as priority habitat types for conservation. We anticipate that our analysis might serve as a model for guiding and standardizing conservation assessments at multiple scales for Odonata and other diverse taxa that have not yet received attention to prioritization. © 2015 by The Society for Freshwater Science.
Hager B.J.,Cazenovia College |
Hunt P.D.,Audubon Society of New Hampshire |
Fox J.N.,Carleton University |
Vowels K.M.,Bernheim Arboretum and Research Forest
Insect Conservation and Diversity | Year: 2012
1.Repeat surveys are needed to capture a representative spectrum of adult odonate richness at a site, but specifics on frequency and duration of surveys and associated inferential biases are poorly understood. 2.Weekly 1h surveys of mature male dragonflies and damselflies were repeated at least 15 times at 19 ponds, lakes and wetlands scattered throughout North America. For each site, we tallied the data remaining when the weekly frequency was reduced to 75% (every 1.5weeks), 50% (biweekly), 33% (triweekly), and 25% (monthly) and the 1h survey to 50, 40, 30, 20 and 10min subsets. 3.Reducing the original effort by half (i.e. to 30min biweekly) retained about 80% of the species on average. The smallest effort (10min monthly) retained about 49% of species. The greatest rate of information loss occurred between 20 and 10min. 4.Across-site analysis found that data subsets correlated to the original data set (r>0.81) despite up to 50% species loss. Strong correlations (r≥0.98) remained with 10-15% species loss. 5.Biweekly surveys lasting 20-40min each may provide a representative and cost-effective sample of adult odonate richness in lentic study sites. Losing a handful of species should not greatly undermine richness and compositional comparisons among sites.. © 2011 The Authors Insect Conservation and Diversity © 2011 The Royal Entomological Society.