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• 1. [Article] Models of presence-absence estimate abundance as well as (or even better than) models of abundance: the case of the butterfly Parnassius apollo

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10980.

  Citation × Citation Citation Abstract Copy Title: Models of presence-absence estimate abundance as well as (or even better than) models of abundance: the case of the butterfly Parnassius apollo Author: Wilson, Robert J., Gutiérrez, David, Díez, Sonia B., Gutiérrez Illán, Javier, Harcourt, Jennifer This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10980. Title: Models of presence-absence estimate abundance as well as (or even better than) models of abundance: the case of the butterfly Parnassius apollo Author: Wilson, Robert J., Gutiérrez, David, Díez, Sonia B., Gutiérrez Illán, Javier, Harcourt, Jennifer This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10980. Close

• 2. [Article] Models of presence-absence estimate abundance as well as (or even better than) models of abundance: the case of the butterfly Parnassius apollo

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10980.

  Citation × Citation Citation Abstract Copy Title: Models of presence-absence estimate abundance as well as (or even better than) models of abundance: the case of the butterfly Parnassius apollo Author: Wilson, Robert J., Gutiérrez, David, Díez, Sonia B., Harcourt, Jennifer, Gutiérrez Illán, Javier This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10980. Title: Models of presence-absence estimate abundance as well as (or even better than) models of abundance: the case of the butterfly Parnassius apollo Author: Wilson, Robert J., Gutiérrez, David, Díez, Sonia B., Harcourt, Jennifer, Gutiérrez Illán, Javier This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10980. Close

• 3. [Article] Effects of plant community characteristics on insect abundance : implications for sage-grouse brood-rearing habitat

  A causative factor in declining greater sage-grouse (Centrocercus urophasianus) populations is reduced annual recruitment due to poor habitat quality. Sage-grouse population decline is concurrent with ...

  Citation × Citation Citation Abstract Copy Title: Effects of plant community characteristics on insect abundance : implications for sage-grouse brood-rearing habitat Author: Ersch, Erica A. A causative factor in declining greater sage-grouse (Centrocercus urophasianus) populations is reduced annual recruitment due to poor habitat quality. Sage-grouse population decline is concurrent with a decline in the extent and quality of the sagebrush (Artemisia sp.) biome. However, current research has shown a positive relationship between sage-grouse brood and chick survival and the abundance of Lepidoptera larva (caterpillars of moths and butterflies). This two-year (2007-2008) study focused on linking the abundance of litter and ground dwelling insects with plant community characteristics in sagebrush steppe ecosystems, in anticipation of improving sage-grouse brood-rearing habitat management. Focus was placed on insects that have been found in the diet of sage-grouse chicks and included ants, grasshoppers, darkling beetles, and scarab beetles, with a special emphasis on caterpillars. Four sites were chosen in central Oregon for this research. Two sites were dominated by A. tridentata ssp. vaseyana (mountain big sagebrush) and were managed under two different seasons of cattle grazing, spring and winter. The remaining two sites were split between a Chrysothamnus viscidiflorus (yellow rabbitbrush) dominated upland and an Ericameria nauseosa (rubber rabbitbrush) dominated meadow. Line-point intercept, plant height, and basal gap intercept were employed to measure plant community structure and composition. Insect abundance was measured two ways: 1) pitfall traps for ground crawling insects, and 2) black light traps to capture adult moths. Identification of Lepidoptera species by caterpillars is difficult; therefore, documenting Lepidoptera species within an area by conducting an inventory of the adults was necessary. Results show the meadow site had more rabbitbrush, shrub, and vegetative cover, as well as taller shrubs and smaller basal gaps than the upland rabbitbrush site. Although the impact of grazing management was not quantified in this study, spring grazed sites exhibited more sagebrush and shrub cover, taller grasses and shrubs, and larger basal gaps when compared to the winter grazed sites. Within the A. tridentata ssp. vaseyana sites, forb cover, total vegetative cover, grass heights, and species richness were different between years. The meadow site provided the highest abundance of caterpillars compared to all other sites. Both rabbitbrush sites provided more caterpillars throughout May and June than the A. tridentata ssp. vaseyana communities, corresponding to early sage-grouse brood-rearing. The winter grazed A. tridentata ssp. vaseyana site and the upland rabbitbrush site exhibited the highest abundance of grasshoppers. Correlations of vegetation characteristics with insect abundance highlighted several relationships: 1) caterpillars were negatively associated with percent basal gap, mean basal gap size, and sagebrush cover, 2) caterpillars were positively associated with perennial grass cover, rabbitbrush cover, shrub height, and total vegetative cover, and 3) darkling beetles were positively associated with annual forb and annual grass cover. Moth abundance and species richness were highest during July, August, and September, with relatively few moths being caught in May or June. Overall, 222 moth species were present at the study location. Rabbitbrush and sagebrush sites had 145 species in common, with the rabbitbrush sites having 194 species overall and A. tridentata ssp. vaseyana sites having 173 species overall. Moth abundance was negatively correlated with perennial grass cover, basal cover, rabbitbrush cover, shrub and grass height, and total vegetative cover. Additionally, moth abundance was positively correlated with basal gap percent and size, as well as sagebrush cover. In conclusion, the upland rabbitbrush site exhibited the highest abundance of moths, whereas the meadow site presented the most diverse and unique number of moth species. The results of this study suggest rabbitbrush communities may be an important and intricate component within the sagebrush-steppe landscape, contributing to the quality of sage-grouse brood-rearing habitat. Title: Effects of plant community characteristics on insect abundance : implications for sage-grouse brood-rearing habitat Author: Ersch, Erica A. A causative factor in declining greater sage-grouse (Centrocercus urophasianus) populations is reduced annual recruitment due to poor habitat quality. Sage-grouse population decline is concurrent with a decline in the extent and quality of the sagebrush (Artemisia sp.) biome. However, current research has shown a positive relationship between sage-grouse brood and chick survival and the abundance of Lepidoptera larva (caterpillars of moths and butterflies). This two-year (2007-2008) study focused on linking the abundance of litter and ground dwelling insects with plant community characteristics in sagebrush steppe ecosystems, in anticipation of improving sage-grouse brood-rearing habitat management. Focus was placed on insects that have been found in the diet of sage-grouse chicks and included ants, grasshoppers, darkling beetles, and scarab beetles, with a special emphasis on caterpillars. Four sites were chosen in central Oregon for this research. Two sites were dominated by A. tridentata ssp. vaseyana (mountain big sagebrush) and were managed under two different seasons of cattle grazing, spring and winter. The remaining two sites were split between a Chrysothamnus viscidiflorus (yellow rabbitbrush) dominated upland and an Ericameria nauseosa (rubber rabbitbrush) dominated meadow. Line-point intercept, plant height, and basal gap intercept were employed to measure plant community structure and composition. Insect abundance was measured two ways: 1) pitfall traps for ground crawling insects, and 2) black light traps to capture adult moths. Identification of Lepidoptera species by caterpillars is difficult; therefore, documenting Lepidoptera species within an area by conducting an inventory of the adults was necessary. Results show the meadow site had more rabbitbrush, shrub, and vegetative cover, as well as taller shrubs and smaller basal gaps than the upland rabbitbrush site. Although the impact of grazing management was not quantified in this study, spring grazed sites exhibited more sagebrush and shrub cover, taller grasses and shrubs, and larger basal gaps when compared to the winter grazed sites. Within the A. tridentata ssp. vaseyana sites, forb cover, total vegetative cover, grass heights, and species richness were different between years. The meadow site provided the highest abundance of caterpillars compared to all other sites. Both rabbitbrush sites provided more caterpillars throughout May and June than the A. tridentata ssp. vaseyana communities, corresponding to early sage-grouse brood-rearing. The winter grazed A. tridentata ssp. vaseyana site and the upland rabbitbrush site exhibited the highest abundance of grasshoppers. Correlations of vegetation characteristics with insect abundance highlighted several relationships: 1) caterpillars were negatively associated with percent basal gap, mean basal gap size, and sagebrush cover, 2) caterpillars were positively associated with perennial grass cover, rabbitbrush cover, shrub height, and total vegetative cover, and 3) darkling beetles were positively associated with annual forb and annual grass cover. Moth abundance and species richness were highest during July, August, and September, with relatively few moths being caught in May or June. Overall, 222 moth species were present at the study location. Rabbitbrush and sagebrush sites had 145 species in common, with the rabbitbrush sites having 194 species overall and A. tridentata ssp. vaseyana sites having 173 species overall. Moth abundance was negatively correlated with perennial grass cover, basal cover, rabbitbrush cover, shrub and grass height, and total vegetative cover. Additionally, moth abundance was positively correlated with basal gap percent and size, as well as sagebrush cover. In conclusion, the upland rabbitbrush site exhibited the highest abundance of moths, whereas the meadow site presented the most diverse and unique number of moth species. The results of this study suggest rabbitbrush communities may be an important and intricate component within the sagebrush-steppe landscape, contributing to the quality of sage-grouse brood-rearing habitat. Close

• 4. [Article] The historic and contemporary ecology of western Cascade meadows : archeology, vegetation, and macromoth ecology

  Montane meadows in the western Cascades of Oregon occupy approximately 5% of the landscape, but contribute greatly to the region's biodiversity. Western Cascades meadows are dynamic parts of the landscape ...

  Citation × Citation Citation Abstract Copy Title: The historic and contemporary ecology of western Cascade meadows : archeology, vegetation, and macromoth ecology Author: Highland, Steven A. Montane meadows in the western Cascades of Oregon occupy approximately 5% of the landscape, but contribute greatly to the region's biodiversity. Western Cascades meadows are dynamic parts of the landscape and have contracted by over 50% in the past two hundred years in the HJ Andrews Experimental Forest (hereafter Andrews Forest). Many studies have linked the loss of meadows with local extirpation of species and loss of regional biodiversity, but these processes depend upon the factors that create and maintain meadows, and how species respond to meadow configuration. The prehistory of these meadows is poorly understood, as is the contemporary ecology. This study combined previously collected archeological and moth datasets, aerial photographs, and new plant, tree core, and moth data to investigate interactions between landforms, disturbance, vegetation, and moth abundance and diversity in montane meadows of the western Cascades of Oregon. Burning by prehistoric people may have created and maintained montane meadows, but relatively little evidence remains of the activities of prehistoric peoples in the western Cascades. This study assessed the extent to which prehistoric people preferentially used different landforms and vegetation types by inferring use from landscape distributions of archaeological sites. Descriptions of 359 previously recorded and four newly discovered archeological sites in the McKenzie River watershed of western Oregon were examined using GIS and chi-square analysis to determine how sites were distributed relative to classified vegetation and landforms of the 3700-km² McKenzie River watershed. The high ridges of the HJ Andrews Experimental Forest were analyzed using air photo change detection and archaeological field surveys to identify how archeological sites were distributed relative to landforms and vegetation communities, including meadows. The field surveys documented physical evidence (archeological sites) confirming Native American use of the meadows and surrounding open forests. The locations of these sites indicate that Native Americans utilized the edges between large open meadows and open forests, as well as gently sloping open meadows. The prior extent of meadows (before air photos) was estimated by dendrochronology of 220 trees along present-day and inferred past meadow edges. Forest age structure and the open-grown forms of Douglas fir suggests a much more open habitat, potentially due to fire, was present more than 200 years ago. Moths are major consumers of vegetation when in caterpillar stage and are food sources for many birds and mammals, and contribute greatly to the insect diversity in a region. Moth species richness and abundance may be associated with the distribution of vegetation communities and seasonal timing, and the conservation of rare moths may depend on the conservation of rare vegetation habitats. A dataset of moths sampled 10 times/year at 20 locations in the 64-km² Andrews Forest over the period 2004-2008 was analyzed using generalized linear mixed models (GLMM), non-metric multidimensional scaling (NMS), multi-response permutation procedure (MRPP), analysis of variance (ANOVA), and two tailed t-test to identify the overall patterns of rare and common moth distribution as well as moth community relationships to structurally and taxonomically derived vegetation classes and seasonality. Five hundred fourteen species and 69,168 macromoth individuals were identified. Moth species abundance and diversity were significantly higher in low elevation coniferous forests than in other vegetation types, according to the GLMM. Sixty-six rare moth species were significantly associated with high elevation open habitats. Species associated with meadows also were significantly more likely to be hardwood or herb-feeders than conifer-feeders as caterpillars, based on ANOVAs. The 26 most common moth species were significantly associated with low elevation coniferous forests and were more likely to be conifer-feeders as caterpillars, based on ANOVAs. Common moth species were significantly more likely to emerge earlier in warmer years than in cooler years, based on a two-tailed t-test. Managing the western Cascades landscape for moth biodiversity and for moth abundance requires maintenance and potentially expansion of rare upland habitats as well as lowland coniferous forests. Montane meadows in the Andrews Forest are contracting in size, but it is not known how these changes have affected moth and plant biodiversity. The rate and pattern of meadow contraction from 1949 to 2005 along the high ridges of the Andrews Forest were analyzed using air photo change detection. Overall meadows contracted by nearly 50% from 1949 to 2005, but rates of meadow loss were much higher for the largest meadow complexes. Plant community diversity in seventeen meadows and the diversity, abundance, and community structure of moths at 98 locations sampled in the summers of 2008, 2009, and 2010 were related to measures of meadow size, isolation, and other variables using cluster analysis (CLA), MRPP, NMS, and generalized additive models (GAMs). Plant diversity in meadows was significantly positively related to meadow area in 1949 and the distance of the meadow from the road, based on GAM analysis. Plant community structure was most closely correlated with meadow area in 1949 and slope, based on CLA, MRPP, and NMS analysis. Calendar day explained the most variation in moth species richness, abundance, and community structure, but the next most important explanatory variables differed according to feeding guild, based on GAMs. Richness, abundance, and community structure of herb-feeding moths was related to meadow area in 1949 and elevation. For angiosperm-feeding moths, area-perimeter ratio in 2005 explained the most variation in richness, abundance, and community structure after calendar day. For gymnosperm-feeding moths, meadow area change from 1949-2005, a variable measuring the amount of increase in coniferous tree cover, explained the most variation in richness, abundance, and community structure after calendar day. The abundance and diversity of herb-feeding moths and meadow plants exhibited a lagged response to habitat loss, which may indicate an extinction debt. In contrast, angiosperm-and gymnosperm-feeding moths responded quickly (within 50 years) to increases in their habitat. Managing for the conservation of biodiversity in the upper elevations of the Andrews Forest will require targeted management strategies for different groups of organisms. Herb-feeding moths and meadow plants will benefit from expansion of open meadow habitat, while angiosperm and gymnosperm-feeders will require the maintenance of edge environments and coniferous forests. Title: The historic and contemporary ecology of western Cascade meadows : archeology, vegetation, and macromoth ecology Author: Highland, Steven A. Montane meadows in the western Cascades of Oregon occupy approximately 5% of the landscape, but contribute greatly to the region's biodiversity. Western Cascades meadows are dynamic parts of the landscape and have contracted by over 50% in the past two hundred years in the HJ Andrews Experimental Forest (hereafter Andrews Forest). Many studies have linked the loss of meadows with local extirpation of species and loss of regional biodiversity, but these processes depend upon the factors that create and maintain meadows, and how species respond to meadow configuration. The prehistory of these meadows is poorly understood, as is the contemporary ecology. This study combined previously collected archeological and moth datasets, aerial photographs, and new plant, tree core, and moth data to investigate interactions between landforms, disturbance, vegetation, and moth abundance and diversity in montane meadows of the western Cascades of Oregon. Burning by prehistoric people may have created and maintained montane meadows, but relatively little evidence remains of the activities of prehistoric peoples in the western Cascades. This study assessed the extent to which prehistoric people preferentially used different landforms and vegetation types by inferring use from landscape distributions of archaeological sites. Descriptions of 359 previously recorded and four newly discovered archeological sites in the McKenzie River watershed of western Oregon were examined using GIS and chi-square analysis to determine how sites were distributed relative to classified vegetation and landforms of the 3700-km² McKenzie River watershed. The high ridges of the HJ Andrews Experimental Forest were analyzed using air photo change detection and archaeological field surveys to identify how archeological sites were distributed relative to landforms and vegetation communities, including meadows. The field surveys documented physical evidence (archeological sites) confirming Native American use of the meadows and surrounding open forests. The locations of these sites indicate that Native Americans utilized the edges between large open meadows and open forests, as well as gently sloping open meadows. The prior extent of meadows (before air photos) was estimated by dendrochronology of 220 trees along present-day and inferred past meadow edges. Forest age structure and the open-grown forms of Douglas fir suggests a much more open habitat, potentially due to fire, was present more than 200 years ago. Moths are major consumers of vegetation when in caterpillar stage and are food sources for many birds and mammals, and contribute greatly to the insect diversity in a region. Moth species richness and abundance may be associated with the distribution of vegetation communities and seasonal timing, and the conservation of rare moths may depend on the conservation of rare vegetation habitats. A dataset of moths sampled 10 times/year at 20 locations in the 64-km² Andrews Forest over the period 2004-2008 was analyzed using generalized linear mixed models (GLMM), non-metric multidimensional scaling (NMS), multi-response permutation procedure (MRPP), analysis of variance (ANOVA), and two tailed t-test to identify the overall patterns of rare and common moth distribution as well as moth community relationships to structurally and taxonomically derived vegetation classes and seasonality. Five hundred fourteen species and 69,168 macromoth individuals were identified. Moth species abundance and diversity were significantly higher in low elevation coniferous forests than in other vegetation types, according to the GLMM. Sixty-six rare moth species were significantly associated with high elevation open habitats. Species associated with meadows also were significantly more likely to be hardwood or herb-feeders than conifer-feeders as caterpillars, based on ANOVAs. The 26 most common moth species were significantly associated with low elevation coniferous forests and were more likely to be conifer-feeders as caterpillars, based on ANOVAs. Common moth species were significantly more likely to emerge earlier in warmer years than in cooler years, based on a two-tailed t-test. Managing the western Cascades landscape for moth biodiversity and for moth abundance requires maintenance and potentially expansion of rare upland habitats as well as lowland coniferous forests. Montane meadows in the Andrews Forest are contracting in size, but it is not known how these changes have affected moth and plant biodiversity. The rate and pattern of meadow contraction from 1949 to 2005 along the high ridges of the Andrews Forest were analyzed using air photo change detection. Overall meadows contracted by nearly 50% from 1949 to 2005, but rates of meadow loss were much higher for the largest meadow complexes. Plant community diversity in seventeen meadows and the diversity, abundance, and community structure of moths at 98 locations sampled in the summers of 2008, 2009, and 2010 were related to measures of meadow size, isolation, and other variables using cluster analysis (CLA), MRPP, NMS, and generalized additive models (GAMs). Plant diversity in meadows was significantly positively related to meadow area in 1949 and the distance of the meadow from the road, based on GAM analysis. Plant community structure was most closely correlated with meadow area in 1949 and slope, based on CLA, MRPP, and NMS analysis. Calendar day explained the most variation in moth species richness, abundance, and community structure, but the next most important explanatory variables differed according to feeding guild, based on GAMs. Richness, abundance, and community structure of herb-feeding moths was related to meadow area in 1949 and elevation. For angiosperm-feeding moths, area-perimeter ratio in 2005 explained the most variation in richness, abundance, and community structure after calendar day. For gymnosperm-feeding moths, meadow area change from 1949-2005, a variable measuring the amount of increase in coniferous tree cover, explained the most variation in richness, abundance, and community structure after calendar day. The abundance and diversity of herb-feeding moths and meadow plants exhibited a lagged response to habitat loss, which may indicate an extinction debt. In contrast, angiosperm-and gymnosperm-feeding moths responded quickly (within 50 years) to increases in their habitat. Managing for the conservation of biodiversity in the upper elevations of the Andrews Forest will require targeted management strategies for different groups of organisms. Herb-feeding moths and meadow plants will benefit from expansion of open meadow habitat, while angiosperm and gymnosperm-feeders will require the maintenance of edge environments and coniferous forests. Close