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• 11. [Article] Abundance, Productivity, and Life History of Fifteenmile Creek Steelhead; Annual Report 2016

  Abstract -- The Fifteenmile Creek watershed in North Central Oregon hosts a native population of steelhead (Oncorhynchus mykiss) that is without influence of previous hatchery augmentation. The Fifteenmile ...

  Citation × Citation Citation Abstract Copy Title: Abundance, Productivity, and Life History of Fifteenmile Creek Steelhead; Annual Report 2016 Abstract -- The Fifteenmile Creek watershed in North Central Oregon hosts a native population of steelhead (Oncorhynchus mykiss) that is without influence of previous hatchery augmentation. The Fifteenmile Creek steelhead are a subpopulation within the Distinct Population Segment (DPS) of the Middle Columbia River steelhead and was listed as ‘threatened’ by the National Marine Fisheries Service (NMFS) first on March 25, 1999 and relisted as a DPS on January 5, 2006. Subsequently, a conservation and recovery management plan was developed for the Middle Columbia River steelhead DPS within Oregon state borders. The goal of the plan is to recover Middle Columbia River steelhead to a level that would allow the removal of threatened status, in addition to providing a long-term goal to recover the population sufficiently to provide sustainable fisheries and other ecological, cultural, social and economic benefits for future generations. The DPS-level recovery plan sets specific recovery goals for the areas within the DPS, which designates Fifteenmile Creek explicitly. The Fifteenmile Creek steelhead population is considered the most inland winter race of steelhead in the Columbia River Basin, as designated by NOAA fisheries. However review of this designation may be necessary at the next Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) status-review because the run-timing of adult steelhead passing Bonneville Dam has been inconsistent with known winter-run steelhead in the area. The population was identified as “must have viable” status by the Interior Columbia Technical Recovery Team (ICTRT), and reaching viable status is essential for achieving DPS delisting. The ICTRT, Recovery Plan, and the Federal Columbia River Power System (FCRPS-BiOp) have all identified this population as high priority for improving precision and accuracy of abundance, productivity, diversity, and spatial structure information. Title: Abundance, Productivity, and Life History of Fifteenmile Creek Steelhead; Annual Report 2016 Abstract -- The Fifteenmile Creek watershed in North Central Oregon hosts a native population of steelhead (Oncorhynchus mykiss) that is without influence of previous hatchery augmentation. The Fifteenmile Creek steelhead are a subpopulation within the Distinct Population Segment (DPS) of the Middle Columbia River steelhead and was listed as ‘threatened’ by the National Marine Fisheries Service (NMFS) first on March 25, 1999 and relisted as a DPS on January 5, 2006. Subsequently, a conservation and recovery management plan was developed for the Middle Columbia River steelhead DPS within Oregon state borders. The goal of the plan is to recover Middle Columbia River steelhead to a level that would allow the removal of threatened status, in addition to providing a long-term goal to recover the population sufficiently to provide sustainable fisheries and other ecological, cultural, social and economic benefits for future generations. The DPS-level recovery plan sets specific recovery goals for the areas within the DPS, which designates Fifteenmile Creek explicitly. The Fifteenmile Creek steelhead population is considered the most inland winter race of steelhead in the Columbia River Basin, as designated by NOAA fisheries. However review of this designation may be necessary at the next Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) status-review because the run-timing of adult steelhead passing Bonneville Dam has been inconsistent with known winter-run steelhead in the area. The population was identified as “must have viable” status by the Interior Columbia Technical Recovery Team (ICTRT), and reaching viable status is essential for achieving DPS delisting. The ICTRT, Recovery Plan, and the Federal Columbia River Power System (FCRPS-BiOp) have all identified this population as high priority for improving precision and accuracy of abundance, productivity, diversity, and spatial structure information. Close

• 12. [Article] Coho Life History in Tide Gated Lowland Streams 2014-2016_OWEB 214-2031

  Abstract -- Coos Watershed Association’s (CoosWA) coho life history in tide gated lowland coastal streams, a life cycle monitoring (LCM) project, adapts and advances a long-term monitoring study initiated ...

  Citation × Citation Citation Abstract Copy Title: Coho Life History in Tide Gated Lowland Streams 2014-2016_OWEB 214-2031 Abstract -- Coos Watershed Association’s (CoosWA) coho life history in tide gated lowland coastal streams, a life cycle monitoring (LCM) project, adapts and advances a long-term monitoring study initiated in 2004 to explicitly examine coho salmon abundance, survival, life histories and habitat use in tide gated coastal lowland streams. Evidence from this project and across the range of coho strongly indicates that connectivity in diverse and dynamic tidal habitats provides alternative rearing pathways critical for the sustainability and recovery of Oregon Coastal (OC) coho stocks. Specifically, this project reestablished innovative PIT tag mark recapture techniques to monitor coho movements and migrations. Temporal and spatial components of over-winter rearing strategies, in relation to habitat use and project effectiveness monitoring, is the focus in these paired study streams. Notably, monitoring was shifted to Willanch Creek from Larson Creek. Juvenile coho diet analyses revealed seasonal and diurnal variation in foraging strategies between early migrating sub-yearlings and yearling smolts across their range in estuarine habitats. These results reveal the fundamental mechanisms that promote increased juvenile coho growth and survival in the estuarine ecotone. In conjunction with prior and current data, results highlight the critical importance of these diverse habitats for recovering viable OC coho populations. Title: Coho Life History in Tide Gated Lowland Streams 2014-2016_OWEB 214-2031 Abstract -- Coos Watershed Association’s (CoosWA) coho life history in tide gated lowland coastal streams, a life cycle monitoring (LCM) project, adapts and advances a long-term monitoring study initiated in 2004 to explicitly examine coho salmon abundance, survival, life histories and habitat use in tide gated coastal lowland streams. Evidence from this project and across the range of coho strongly indicates that connectivity in diverse and dynamic tidal habitats provides alternative rearing pathways critical for the sustainability and recovery of Oregon Coastal (OC) coho stocks. Specifically, this project reestablished innovative PIT tag mark recapture techniques to monitor coho movements and migrations. Temporal and spatial components of over-winter rearing strategies, in relation to habitat use and project effectiveness monitoring, is the focus in these paired study streams. Notably, monitoring was shifted to Willanch Creek from Larson Creek. Juvenile coho diet analyses revealed seasonal and diurnal variation in foraging strategies between early migrating sub-yearlings and yearling smolts across their range in estuarine habitats. These results reveal the fundamental mechanisms that promote increased juvenile coho growth and survival in the estuarine ecotone. In conjunction with prior and current data, results highlight the critical importance of these diverse habitats for recovering viable OC coho populations. Close

• 13. [Article] Seven Basins Watershed Assessment

  Abstract -- The watershed assessment includes the topics: a brief history of the Seven Basins Watershed, channel habitat type classification, hydrology and water uses, riparian/wetlands assessment, impact ...

  Citation × Citation Citation Abstract Copy Title: Seven Basins Watershed Assessment Abstract -- The watershed assessment includes the topics: a brief history of the Seven Basins Watershed, channel habitat type classification, hydrology and water uses, riparian/wetlands assessment, impact of wildfire, sediment sources, channel modification assessment, water quality, fish assessment, and summary of watershed conditions. Title: Seven Basins Watershed Assessment Abstract -- The watershed assessment includes the topics: a brief history of the Seven Basins Watershed, channel habitat type classification, hydrology and water uses, riparian/wetlands assessment, impact of wildfire, sediment sources, channel modification assessment, water quality, fish assessment, and summary of watershed conditions. Close

• 14. [Article] Miami River Watershed Assessment

  Abstract -- This assessment looks at watershed history and characteristics, fisheries, aquatic and riparian habitat, hydrology, water use and quality, and sediment sources for the Miami River basin in ...

  Citation × Citation Citation Abstract Copy Title: Miami River Watershed Assessment Abstract -- This assessment looks at watershed history and characteristics, fisheries, aquatic and riparian habitat, hydrology, water use and quality, and sediment sources for the Miami River basin in the Tillamook Bay watershed. A summary and recommendations are given. Title: Miami River Watershed Assessment Abstract -- This assessment looks at watershed history and characteristics, fisheries, aquatic and riparian habitat, hydrology, water use and quality, and sediment sources for the Miami River basin in the Tillamook Bay watershed. A summary and recommendations are given. Close

• 15. [Article] Bear Creek Watershed Assessment, Phase II - Bear Creek Tributary Assessment

  Abstract -- This document assesses 21 tributary sub-basins in the Bear Creek watershed in terms of history, physiography and physical structure, human demographic characteristics, channel morphology, and ...

  Citation × Citation Citation Abstract Copy Title: Bear Creek Watershed Assessment, Phase II - Bear Creek Tributary Assessment Abstract -- This document assesses 21 tributary sub-basins in the Bear Creek watershed in terms of history, physiography and physical structure, human demographic characteristics, channel morphology, and riparian habitat. It concludes with a comparison, and technical prioritization, of conditions across sub-basins. Title: Bear Creek Watershed Assessment, Phase II - Bear Creek Tributary Assessment Abstract -- This document assesses 21 tributary sub-basins in the Bear Creek watershed in terms of history, physiography and physical structure, human demographic characteristics, channel morphology, and riparian habitat. It concludes with a comparison, and technical prioritization, of conditions across sub-basins. Close

• 16. [Article] Salmonberry River Temperature Monitoring-STEP Project

  Abstract -- Results of a STEP project in which volunteers monitor summer temperatures in the Salmonberry River and tributaries. The project began collecting temperatures in 1994. Project history, protocol, ...

  Citation × Citation Citation Abstract Copy Title: Salmonberry River Temperature Monitoring-STEP Project Abstract -- Results of a STEP project in which volunteers monitor summer temperatures in the Salmonberry River and tributaries. The project began collecting temperatures in 1994. Project history, protocol, and results are summarized in pdf documents. Title: Salmonberry River Temperature Monitoring-STEP Project Abstract -- Results of a STEP project in which volunteers monitor summer temperatures in the Salmonberry River and tributaries. The project began collecting temperatures in 1994. Project history, protocol, and results are summarized in pdf documents. Close

• 17. [Article] Upper Owyhee Watershed Assessment

  Abstract -- The 2011 Upper Owyhee Watershed Assessment was produced by the Owyhee Watershed Council and Scientific Ecological Services Inc. The purpose of the document is to discuss components of the watershed, ...

  Citation × Citation Citation Abstract Copy Title: Upper Owyhee Watershed Assessment Abstract -- The 2011 Upper Owyhee Watershed Assessment was produced by the Owyhee Watershed Council and Scientific Ecological Services Inc. The purpose of the document is to discuss components of the watershed, a brief overview, history of the area and the watershed's condition. Title: Upper Owyhee Watershed Assessment Abstract -- The 2011 Upper Owyhee Watershed Assessment was produced by the Owyhee Watershed Council and Scientific Ecological Services Inc. The purpose of the document is to discuss components of the watershed, a brief overview, history of the area and the watershed's condition. Close

• 18. [Article] Recovery of Wild Coho Salmon In Salmon River Basin, 2008-2010 Report Number: OPSW-ODFW-2011-10

  Abstract -- Hatcheries have been a centerpiece of salmon management in the Pacific Northwest for more than a century but recent evidence of adverse interactions between hatchery and naturally-produced ...

  Citation × Citation Citation Abstract Copy Title: Recovery of Wild Coho Salmon In Salmon River Basin, 2008-2010 Report Number: OPSW-ODFW-2011-10 Abstract -- Hatcheries have been a centerpiece of salmon management in the Pacific Northwest for more than a century but recent evidence of adverse interactions between hatchery and naturally-produced salmon have resulted in substantial changes in many hatchery programs. In 2007 the Oregon Department of Fish and Wildlife terminated a 30-year artificial propagation program for coho salmon in the Salmon River basin after a status assessment concluded that wild population viability was threatened by hatchery effects on salmon productivity (Chilcote et al. 2005). Hatchery-reared coho comprised 50-100% of the naturally spawning population in recent years. Low productivity was reflected in a low spawner to recruit ratio, and life-stage specific survival was lower than that of nearby populations. The temporal distribution of adult spawning in the basin was truncated and peaked 1.5 months earlier relative to the pre-hatchery period and adjacent coastal populations. The cessation of hatchery releases into Salmon River not only removed the primary factor believed to limit productivity of the local population, it also constituted a rare management experiment to test whether a naturally-spawning population can recover from a prolonged period of low abundance after interactions with hatchery-produced coho salmon are eliminated. This report summarizes the results of coho population studies at Salmon River for the first three years after the hatchery program was discontinued. The study in Salmon River is timely because ecological interactions between hatchery and wild fish have been implicated in the reduced survival and decreased productivity of wild coho and other salmonid populations (Nickelson 2003, Buhle et al. 2009, Chilcote et al. 2011). Recent studies involving a diversity of salmonid species and watersheds have shown a negative relationship between hatchery spawner abundance and wild population productivity regardless of the duration of hatchery influence (Chilcote et al. 2011). Yet neither the mechanisms of these productivity declines nor their potential reversibility have been investigated. Recent management changes at Salmon River provide an opportunity to experimentally evaluate coho salmon survival and productivity following the elimination of a decades-long hatchery program. The results will provide new insights into the reversibility of hatchery effects and the rate, mechanisms, and trajectory of response by a naturally spawning coho salmon population. Hatchery programs have been shown to change the timing and distribution of naturally spawning adults, but ecological and genetic influences on the spatial structure and life history diversity of juvenile populations are poorly understood. Conventional understanding of the life history of juvenile coho has presumed a relatively fixed pattern of rearing and migration. However, recent studies have found much greater variation in juvenile life history and habitat-use patterns than previously expected (Miller and Sadro 2003, Koski 2009), including evidence that estuaries may play a prominent role in the life histories of some coho salmon populations. A recent study in the Salmon River basin found considerable diversity in the life histories of juvenile Chinook salmon, including extended rearing by fry and other subyearling migrants within the complex network of natural and restored estuarine wetlands (Bottom et al. 2005). Unfortunately, interpretation of juvenile life history variations at Salmon River was confounded by the Chinook hatchery program, which has concentrated spawning activity in the lower river near the hatchery and may directly influence juvenile migration and rearing patterns. Discontinuation of the coho hatchery program at Salmon River provides an opportunity to quantify changes in juvenile life history following the elimination of all hatchery-fish interactions with the naturally spawning population. Such responses may provide important insights into the mechanisms of hatchery influence on wild salmon productivity and population resilience. Our research integrates adult and juvenile life stages, examines linkages to physical habitat conditions in fresh water and the estuary, and describes variability between juvenile performance and adult returns. It also monitors the coho salmon population across habitat types and life history stages to identify population responses at a landscape scale. We will determine productivity and survival at each salmon life stage and monitor the response of the adult population following the cessation of the coho salmon hatchery program. From these indicators, we will determine the potential resiliency of the coho salmon population, and evaluate the biological benefits or tradeoffs of returning the ecosystem to natural salmon production. Our study design encompasses four population phases: (1) pre-hatchery conditions (Mullen 1979), (2) dominance by hatchery-reared spawners (2008), (3) first generation naturally produced juveniles (2009-2011), and (4) second generation naturally produced juveniles (starting in 2012). This research will validate assumptions about factors limiting coho recovery and determine whether recovery actions have been effective. Here, we report on findings from 2008-2010 to address four principal objectives: 1. Quantify life stage specific survival and recruits per spawner ratio of the coho salmon population before and after hatchery coho salmon are removed from Salmon River. 2. Assess whether the Salmon River coho population is limited by capacity and complexity of stream habitat. 3. Describe the diversity of juvenile and adult life histories of coho salmon in the Salmon River basin, and estimate the relative contributions of various juvenile life histories to adult returns. 4. Determine seasonal use of the Salmon River estuary and its tidally-inundated wetlands by juvenile coho salmon. The field sampling that supported the study on coho salmon also captured Chinook salmon and steelhead and cutthroat trout during routine sampling in the watershed and estuary. This report emphasizes coho salmon results, but also summarizes catch, distribution, and migration data for other salmonids to compare densities and abundances in freshwater and the estuary. Additional results for Chinook, steelhead, and cutthroat are presented in Appendix A. See Stein et al. (2011) for more detailed information on life history diversity, migration patterns, habitat use, and abundance of cutthroat trout. Title: Recovery of Wild Coho Salmon In Salmon River Basin, 2008-2010 Report Number: OPSW-ODFW-2011-10 Abstract -- Hatcheries have been a centerpiece of salmon management in the Pacific Northwest for more than a century but recent evidence of adverse interactions between hatchery and naturally-produced salmon have resulted in substantial changes in many hatchery programs. In 2007 the Oregon Department of Fish and Wildlife terminated a 30-year artificial propagation program for coho salmon in the Salmon River basin after a status assessment concluded that wild population viability was threatened by hatchery effects on salmon productivity (Chilcote et al. 2005). Hatchery-reared coho comprised 50-100% of the naturally spawning population in recent years. Low productivity was reflected in a low spawner to recruit ratio, and life-stage specific survival was lower than that of nearby populations. The temporal distribution of adult spawning in the basin was truncated and peaked 1.5 months earlier relative to the pre-hatchery period and adjacent coastal populations. The cessation of hatchery releases into Salmon River not only removed the primary factor believed to limit productivity of the local population, it also constituted a rare management experiment to test whether a naturally-spawning population can recover from a prolonged period of low abundance after interactions with hatchery-produced coho salmon are eliminated. This report summarizes the results of coho population studies at Salmon River for the first three years after the hatchery program was discontinued. The study in Salmon River is timely because ecological interactions between hatchery and wild fish have been implicated in the reduced survival and decreased productivity of wild coho and other salmonid populations (Nickelson 2003, Buhle et al. 2009, Chilcote et al. 2011). Recent studies involving a diversity of salmonid species and watersheds have shown a negative relationship between hatchery spawner abundance and wild population productivity regardless of the duration of hatchery influence (Chilcote et al. 2011). Yet neither the mechanisms of these productivity declines nor their potential reversibility have been investigated. Recent management changes at Salmon River provide an opportunity to experimentally evaluate coho salmon survival and productivity following the elimination of a decades-long hatchery program. The results will provide new insights into the reversibility of hatchery effects and the rate, mechanisms, and trajectory of response by a naturally spawning coho salmon population. Hatchery programs have been shown to change the timing and distribution of naturally spawning adults, but ecological and genetic influences on the spatial structure and life history diversity of juvenile populations are poorly understood. Conventional understanding of the life history of juvenile coho has presumed a relatively fixed pattern of rearing and migration. However, recent studies have found much greater variation in juvenile life history and habitat-use patterns than previously expected (Miller and Sadro 2003, Koski 2009), including evidence that estuaries may play a prominent role in the life histories of some coho salmon populations. A recent study in the Salmon River basin found considerable diversity in the life histories of juvenile Chinook salmon, including extended rearing by fry and other subyearling migrants within the complex network of natural and restored estuarine wetlands (Bottom et al. 2005). Unfortunately, interpretation of juvenile life history variations at Salmon River was confounded by the Chinook hatchery program, which has concentrated spawning activity in the lower river near the hatchery and may directly influence juvenile migration and rearing patterns. Discontinuation of the coho hatchery program at Salmon River provides an opportunity to quantify changes in juvenile life history following the elimination of all hatchery-fish interactions with the naturally spawning population. Such responses may provide important insights into the mechanisms of hatchery influence on wild salmon productivity and population resilience. Our research integrates adult and juvenile life stages, examines linkages to physical habitat conditions in fresh water and the estuary, and describes variability between juvenile performance and adult returns. It also monitors the coho salmon population across habitat types and life history stages to identify population responses at a landscape scale. We will determine productivity and survival at each salmon life stage and monitor the response of the adult population following the cessation of the coho salmon hatchery program. From these indicators, we will determine the potential resiliency of the coho salmon population, and evaluate the biological benefits or tradeoffs of returning the ecosystem to natural salmon production. Our study design encompasses four population phases: (1) pre-hatchery conditions (Mullen 1979), (2) dominance by hatchery-reared spawners (2008), (3) first generation naturally produced juveniles (2009-2011), and (4) second generation naturally produced juveniles (starting in 2012). This research will validate assumptions about factors limiting coho recovery and determine whether recovery actions have been effective. Here, we report on findings from 2008-2010 to address four principal objectives: 1. Quantify life stage specific survival and recruits per spawner ratio of the coho salmon population before and after hatchery coho salmon are removed from Salmon River. 2. Assess whether the Salmon River coho population is limited by capacity and complexity of stream habitat. 3. Describe the diversity of juvenile and adult life histories of coho salmon in the Salmon River basin, and estimate the relative contributions of various juvenile life histories to adult returns. 4. Determine seasonal use of the Salmon River estuary and its tidally-inundated wetlands by juvenile coho salmon. The field sampling that supported the study on coho salmon also captured Chinook salmon and steelhead and cutthroat trout during routine sampling in the watershed and estuary. This report emphasizes coho salmon results, but also summarizes catch, distribution, and migration data for other salmonids to compare densities and abundances in freshwater and the estuary. Additional results for Chinook, steelhead, and cutthroat are presented in Appendix A. See Stein et al. (2011) for more detailed information on life history diversity, migration patterns, habitat use, and abundance of cutthroat trout. Close

• 19. [Article] Donner und Blitzen Sub-basin Watershed Assessment

  Abstract -- The 2003 Donner und Blitzen Sub-basin Watershed Assessment was prepared by the Harney County Watershed Council. The Donner und Blitzen Sub-Basin is 505,127 acres located in Harney County, Oregon. ...

  Citation × Citation Citation Abstract Copy Title: Donner und Blitzen Sub-basin Watershed Assessment Abstract -- The 2003 Donner und Blitzen Sub-basin Watershed Assessment was prepared by the Harney County Watershed Council. The Donner und Blitzen Sub-Basin is 505,127 acres located in Harney County, Oregon. The Donner und Blitzen Sub-basin has 1,391 miles of streams within its 174 mile perimeter. The document discusses history of the sub-basin and the historical land uses. Following history and description, the results of the assessments are discussed and related to the land and resource use of the sub-basin and the current watershed issues based on those uses. The end of the document discussed the proposed changes to the sub-basin based on assessment results in relation to current and past land resouce use and the goals of the Harney County Watershed Council. Title: Donner und Blitzen Sub-basin Watershed Assessment Abstract -- The 2003 Donner und Blitzen Sub-basin Watershed Assessment was prepared by the Harney County Watershed Council. The Donner und Blitzen Sub-Basin is 505,127 acres located in Harney County, Oregon. The Donner und Blitzen Sub-basin has 1,391 miles of streams within its 174 mile perimeter. The document discusses history of the sub-basin and the historical land uses. Following history and description, the results of the assessments are discussed and related to the land and resource use of the sub-basin and the current watershed issues based on those uses. The end of the document discussed the proposed changes to the sub-basin based on assessment results in relation to current and past land resouce use and the goals of the Harney County Watershed Council. Close

• 20. [Article] Coho Life History in Tide Gated Lowland Coastal Streams

  Abstract -- Coos Watershed Association’s (CoosWA) coho Life Cycle Monitoring Project (LCM) is a continuation of a long-term monitoring study initiated in 2004 to examine coho salmon abundance, survival, ...

  Citation × Citation Citation Abstract Copy Title: Coho Life History in Tide Gated Lowland Coastal Streams Abstract -- Coos Watershed Association’s (CoosWA) coho Life Cycle Monitoring Project (LCM) is a continuation of a long-term monitoring study initiated in 2004 to examine coho salmon abundance, survival, life histories and habitat use in two tide gated coastal lowland streams, Larson and Palouse Creeks. Productive utilization of these remarkable habitat types is critical for the recovery and sustainability of Oregon Coastal coho. Specifically, this project developed, and adapted innovative mark recapture techniques using PIT tags to monitor the coho life cycle, further evaluated over-winter rearing strategies in relation to temporal and spatial habitat use and continued project effectiveness monitoring in these study streams. In addition, coho diet analyses were designed and conducted and will be analyzed in relation to seasonal and diurnal variations in environmental factors in order to assess proximal causes of habitat productivity. Title: Coho Life History in Tide Gated Lowland Coastal Streams Abstract -- Coos Watershed Association’s (CoosWA) coho Life Cycle Monitoring Project (LCM) is a continuation of a long-term monitoring study initiated in 2004 to examine coho salmon abundance, survival, life histories and habitat use in two tide gated coastal lowland streams, Larson and Palouse Creeks. Productive utilization of these remarkable habitat types is critical for the recovery and sustainability of Oregon Coastal coho. Specifically, this project developed, and adapted innovative mark recapture techniques using PIT tags to monitor the coho life cycle, further evaluated over-winter rearing strategies in relation to temporal and spatial habitat use and continued project effectiveness monitoring in these study streams. In addition, coho diet analyses were designed and conducted and will be analyzed in relation to seasonal and diurnal variations in environmental factors in order to assess proximal causes of habitat productivity. Close