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The adaptive radiation of the Hawaiian honeycreepers is the largest ever recorded for birds on an oceanic archipelago. Despite including >50 species in 21 genera, no hybridizations across honeycreeper species have ever been confirmed. Here, we report genetic and morphological analyses that verify the first hybrid between two Hawaiian honeycreeper species: the 'I'iwi (Vestiaria coccinea) and 'Apapane CHimatione sanguinea). This hybridization is notable given that the parental species diverged -1.6 mya and show distinct morphological differences. Further, this discovery is important in light of recent evidence that hybridization plays an important role in speciation and genetic diversity in both plants and animals. Received 2 April 2013. Accepted 5 April 2014. Key words: adaptive radiation, Big Island of Hawaii, Drepanididae, intergeneric hybrid, microsatellites, 454 sequencing., The adaptive radiation of the Hawaiian honeycreepers (Fringillidae: Drepanidinae), with 21 genera and more than 50 species, is the largest avian radiation on an oceanic archipelago (Pratt et al. 2009). [...]

Taxus canadensis Marsh., a shade-tolerant evergreen shrub, is in decline as a result of past anthropogenic disturbances and increased cervid browsing. To identify factors that may be influencing establishment for this species, we planted 1080 T. canadensis cuttings in a hemlock-hardwood forest in the spring of 2004. Cuttings were planted across a gradient of light environments, consisting of artificial canopy gaps (61-441 [m.sup.2]) and closed-canopy conditions, and half were protected with deer exclosures. Following four growing seasons, T. canadensis survival in exclosures was 92% compared with 75% in controls. A mixed-effects binary logistic regression analysis revealed that deer exclusion had the most influence on the probability of survival; all else being equal an individual was nearly seven times more likely to survive if planted inside an exclosure (P < 0.001). Increasing light intensity had a counterbalancing effect on growth and survival; light increased leader growth (P = 0.019) but reduced an individual's probability of survival (P < 0.001), possibly owing to enhanced herbivory and elevated moisture stress. Consequently, enhancing resource availability and growth may not decrease the impact of biomass loss to herbivory. These results suggest that even with relatively low herbivore densities, exclosures are required for the recovery of highly palatable species. Taxus canadensis Marsh. un arbuste sempervirent et tolerant a l'ombre, connait un declin a cause de perturbations anthropogeniques passees et du broutement accru des cervides. Dans le but d'identifier les facteurs qui peuvent influencer l'etablissement de cette espece, nous avons plante 1080 boutures de T. canadensis dans une foret de pruche et de feuillus au printemps 2004. Les boutures ont ete plantees le long d'un gradient de luminosite, dans des trouees artificielles dans la canopee (61-441 [m.sup.2]) et sous couvert ferme. La moitie des boutures ont ete protegees des chevreuils par des exclos. Apres quatre saisons de croissance, la survie de T. canadensis atteignait 92% dans les exclos comparativement a 75 % dans les parcelles temoins. Une analyse de regression logistique binaire a effets mixtes a revele que l'exclusion des chevreuils avait le plus d'influence sur la probabilite de survie : tous les autres facteurs etant egaux, un individu avait presque sept fois plus de chances de survivre en etant plante a l'interieur d'un exclos (P < 0,001). Le fait d'augmenter l'intensite lumineuse a eu un effet de compensation entre la croissance et la survie : la lumiere a augmente la croissance de la pousse terminale (P = 0,019) mais a reduit la probabilite qu'un individu survive (P < 0,001), possiblement a cause du broutement accru et de l'augmentation du stress hydrique. Par consequent, le fait d'ameliorer la disponibilite des ressources et la croissance peut ne pas reduire l'impact de la perte de biomasse due au broutement. Ces resultats indiquent que meme avec une densite relativement faible d'herbivores, des exclos sont necessaires pour assurer la recuperation des especes tres appetentes. [Traduit par la Redaction], Introduction In forest ecosystems woody shrubs face many challenges in the struggle for survival and growth. In addition to coping with the high-shade environment of the forest floor (Oliver and [...]

Canada yew (Taxus canadensis Marsh.) is a shade-tolerant evergreen shrub native to the understories of the boreal and deciduous forests of northeastern North America. Canada yew has a relatively unique growth form, with low sprawling branches capable of forming dense clusters of stems. Historic accounts suggest that before Euro-American settlement, Canada yew was a common plant across its range in many forest types and that it was locally abundant or dominant in 5%-20% of forest stands in the northern part of its range. Canada yew's range has declined during the last century as a result of browsing by native ungulates, fire, intensive forest management, and clearing of land for agriculture and other development. It is considered uncommon throughout most of its present North American range, except for often isolated populations in areas that remain free from heavy browsing pressure by moose and deer (e.g., islands, areas with heavy snow cover, or areas naturally low in ungulate abundance). Its decline has likely resulted in changes to abiotic and biotic conditions, including structure and composition of understory vegetation and concomitant effects on understory vertebrates. Increasing white-tailed deer populations and reduced snowfall as a result of climate change in eastern North America threaten to extirpate this species from additional parts of its range in the next century. Suggestions for future research are discussed. Key words: autecology, Canada yew, Taxus canadensis, distribution, white-tailed deer, browsing effects. L'if du Canada (Taxus canadensis Marsh.), un arbuste nain toujours vert et tolerant l'ombre, est indigene dans les sous-bois de forests boreales et decidues de nord-est de l'Amerique. L'if du Canada montre une forme de croissance relativement unique, avec ses longues branches trainantes capables de former des groupes de tiges. Les donnees historiques suggerent qu'avant l'arriveee des Europeeens au Canada, l'if constituait une plante commune sur l'ensemble de son aire dans plusieurs types de forets et qu'il eetait localement abondant ou dominant dans 5-20 % des peuplements forestiers dans la partie nord de son aire. L'aire de l'if du Canada a decline au cours du dernier siecle, suite au broutage par les ongules indigenes, au feu, a l'amenagement intensif des forets, et au defrichage des sols aux fins de l'agriculture et autres developpements. On le considere comme peu commun sur l'ensemble de son aire nord-americaine actuelle, sauf pour des populations souvent isolees dans les regions qui demeurent a l'abri du broutage intensif par les orignaux et les cerfs de Virginie (e.g., iles, regions avec fort couvert de neige, ou regions naturellement a faible abondance d'ongulees). Son deeclin a vraisemblablement fait suite a des changements abiotiques et biotiques, incluant la structure et la composition de la vegetation de sous-bois, et leurs effets concomitants sur les vertebres des sous-bois. Une augmentation des populations du cerf de Virginie et une reduction des couverts de neige suite aux changements climatiques dans l'est de l'Amerique du Nord menacent cette espece d'extirpation sur d'autres parties de son aire au cours du prochain siecle. Les auteurs proposent des suggestions pour les recherches futures. Mots-cles: auteecologie, if du Canada, Taxus canadensis, distribution, cerf de Virginie, effet du broutage. [Traduit par la Redaction], 1. Introduction Canada yew (Taxus canadensis Marsh.), a formerly wide-spread evergreen forest shrub, is of conservation interest for several reasons. First, its decline is frequently cited as an ex ample [...]

Human development on lakeshore habitats has greatly reduced shrub layer coverage along many North American lakes, negatively impacting associated floral and faunal communities. In northern Wisconsin, several restoration projects have been implemented in recent decades to reverse the impacts of development on lakeshore natural communities. However, restoration practitioners are frequently limited to using containerized plant stock purchased at local nurseries, which can be cost-prohibitive. As an alternative, we tested the effectiveness of using dormant bare-root shrubs in restoration projects along five lakeshores in northern Wisconsin. Because bare-root plant stock can only be planted during narrow windows during the late fall and early spring, we examined the efficacy of using bare-root stock that was grown in a gravel medium ("gravel-culture") and then planted later during the growing season. We monitored individuals from five species of native shrubs in each of three planting treatments over a three-year period and used a repeated measures, mixed-model approach to compare plant growth of both bare-root and gravel culture stock to growth of containerized stock. Logistic regression models were used to compare the survival of shrubs and treatments. Containerized stock exhibited the greatest growth and survival of the stock types examined. The utility of bare-root and gravel-culture stock varied among species, but for most species our results suggest that gravel-culture may be successfully used to extend the planting window. [ABSTRACT FROM AUTHOR]

Many birds have advanced their spring migration and breeding phenology in response to climate change, yet some long-distance migrants appear constrained in their adjustments. In addition, bird species with long generation times and those in higher trophic positions may also be less able to track climate-induced shifts in food availability. Migratory birds of prey may therefore be particularly vulnerable to climate change because: 1) most are long-lived and have relatively low reproductive capacity, 2) many feed predominately on insectivorous passerines, and 3) several undertake annual migrations totaling tens of thousands of kilometers. Using multi-decadal datasets for 14 raptor species observed at six sites across the Great Lakes region of North America, we detected phenological shifts in spring migration consistent with decadal climatic oscillations and global climate change. While the North Atlantic and El Niño Southern Oscillations exerted heterogeneous effects on the phenology of a few species, arrival dates more generally advanced by 1.18 d per decade, a pattern consistent with the effects of global climate change. After accounting for heterogeneity across observation sites, five of the 10 most abundant species advanced the bulk of their spring migration phenology. Contrary to expectations, we found that long-distance migrants and birds with longer generation times tended to make the greatest advancements to their spring migration. Such results may indicate that phenotypic plasticity can facilitate climatic responses among these long-lived predators. [ABSTRACT FROM AUTHOR]