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Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional ...
Citation Citation
- Title:
- Habitat use and movement behavior of Pacific marten (Martes caurina) in response to forest management practices in Lassen National Forest, California
- Author:
- Moriarty, Katie M.
Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional understanding of how individuals of those species interact with their environment, specifically how their movement is affected by human-induced changes. In order to maintain connectivity and viable populations, public land managers require science to inform how changes in structure affect the individual movements and thus population connectivity of sensitive species. I collected detailed movement data on Pacific martens (Martes caurina) in Lassen National Forest, California, during 2010-2013. Martens are small carnivores that are closely associated with old forest elements (e.g., large snags and logs). Marten populations rapidly decline with loss and fragmentation of forest cover. As such, martens are a U.S. Forest Service Management Indicator Species and a Species of Special Concern in the state of California. My goal was to understand martens' behavior in forest patches that were altered by thinning to remove ladder fuels-small diameter trees, understory vegetation, and branches near the ground. Such fuels treatments are increasingly prevalent on public lands, especially in dry forests, to reduce risk of high-severity and high-intensity fire. Although previous research suggested martens selection for dense forest and avoid gaps in forest cover, no information was available describing martens' use of simplified thinned patches. The objectives of my dissertation were to: (1) test whether marten movement and activity could accurately be measured using miniature GPS collars, and (2) evaluate marten use, selection, and behavior in patches that differed in structural complexity. Global positioning system (GPS) telemetry provides opportunities to collect detailed information from free-ranging animals with a high degree of precision and accuracy. Miniature GPS collars (42-60g) have only been available since 2009 for mammals and have not been consistently effective. Furthermore, all GPS units suffer from non-random data loss and location error, which is often exacerbated by dense vegetation. Given these constraints, it was questionable whether GPS collars would be an effective tool for studying martens. In Chapter 1, I evaluated how satellite data and environmental conditions affected performance of GPS units. I used a paired experimental design and programmed the GPS unit to retain or remove satellite data before attempting a location (fix). I found that short intervals between fix attempts significantly increased the likelihood of fix success. Locations estimated using at least 4 satellites were, on average, within 28 m of the actual location regardless of vegetation cover. Thus, location estimates at short intervals with >4 satellites were not typically biased by dense vegetation. Accurate fine-scale information on martens was necessary to quantify and interpret patch use and habitat selection. I evaluated martens’ use and behavior in three forest patch types that differed in structural complexity (complex, simple, and open). In Chapter 2, I quantified use patch use in two seasons–summer and winter. I used food-titration experiments to standardize motivation of martens to enter different patch types and compared these short-term incentivized experiments with year-round observational telemetry data (GPS and very high frequency telemetry). Martens selected complex patches and avoided both simple patches and openings, but not equivalently–openings were strongly avoided. With baited incentive, martens were more likely to enter simple patches and openings during winter, when deep snow was present. Because marten patch use differed during winter, I concluded that researchers should use caution when using seasonally collected data to create year-round habitat models. Overall, movement was most limited during summer when predation risk likely deterred martens from moving through simple patches and openings. In Chapter 3, I quantified habitat selection and marten behavior using fine-scale movement data. I evaluated movement-based habitat selection at two scales: (1) selection of home ranges within landscapes and (2) selection of patches within the home ranges. I characterized marten movement patterns and tested whether variance, speed, and sinuosity of movements differed by patch, sex, and season. Martens selected home ranges with fewer openings than available in the landscape, and selected complex patches over simple patches and openings within their home range. On average, martens moved approximately 7 km per day and greater than 1 km per hour – which is notably high for a 600-1000g mammal. Martens moved more slowly, consistently, and sinuously in complex patches. In openings, martens traveled linearly with greater variance in their speed. In simple patches, movement generally was linear and rapid with some variation. I hypothesized that martens used complex patches for foraging and acquisition of resources, traveled through simple patches with the potential for infrequent foraging bouts, and very infrequently crossed openings. Although I found some differences in movement behavior between sexes and seasons, behavior was generally consistent for both sexes in different patch types. I provide general conclusions in Chapter 4 and discuss considerations for future research and management.
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4702. [Article] Impacts of earlier emerging steelhead fry of hatchery origin on the social structure, distribution, and growth of wild steelhead fry
Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and wild origins were studied in laboratory stream channels and natural streams. Objectives of the study were to determine if and how earlier emerging ...Citation Citation
- Title:
- Impacts of earlier emerging steelhead fry of hatchery origin on the social structure, distribution, and growth of wild steelhead fry
- Author:
- Noble, Sandra M. (Sandra Marie)
Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and wild origins were studied in laboratory stream channels and natural streams. Objectives of the study were to determine if and how earlier emerging hatchery fry influence the emigration, realized densities, growth, habitat use, social structure, and activity patterns of localized populations of wild steelhead fry when the hatchery fry have a competitive advantage conferred by larger size and prior residence. During 1986 and 1987, the above variables were observed daily among hatchery and wild steelhead fry in laboratory stream channels for 8 weeks following emergence in June. The habitat use and social activities for fry of both origins were observed weekly in natural stream reaches from June through August in 1987 to corroborate lab findings. In lab channels, both hatchery and wild fry received 2 treatments: living alone (allopatry) and living together (sympatry). In the lab, fry of hatchery origin emerged 7 to 10 d prior to wild fry and remained larger in size during the 8 weeks of study both years. In natural stream reaches, fry of each origin were observed only in allopatric situations. Wild fry in the field emerged from natural redds while hatchery fry were released in stream reaches as unfed, newly emerged (swim-up) fry. Hatchery and wild fry in lab sections were found to be very similar in their emigration rates, distances to nearest neighbor, growth rates, and use of habitat. Both fry types, regardless of treatment or environment (lab or field), established similar stable social structure and used the same types of aggressive acts. Among all lab groups, once a fry became dominant, it retained that social status to the end of the study period. Significant differences (P<.05 both years) among comparison tests were: 1) in allopatric lab sections, wild fry maintained larger densities than hatchery fry, 2) in sympatry, hatchery fry had a greater tendency to establish stable focal points and social hierarchies more readily, defend larger areas, have better condition, prefer pools with overhead cover more frequently, be more aggressive, and reach stable densities more quickly than the wild fry, 3) fewer hatchery fry in sympatry maintained nomadic positions than wild fry in both treatments, 4) in sympatry, hatchery fry directed more acts of overt aggression toward wild fry than other hatchery fry, 5) wild fry in sympatry usually used defensive or less offensive acts of aggression when interacting with other fry, 6) fry of both origins in natural stream reaches maintained greater distances to their nearest neighbor than fry in allopatric lab sections, 7) dominant hatchery fry in both treatments maintained larger focal areas than subdominant fry, 8) hatchery fry maintained longer lengths than wild fry through the duration of the study, and 9) hatchery fry were more aggressive in sympatry than in allopatry. Potential differences (P<.05 in one year and P<.1 in the other year) were: 1) wild fry in sympatry had lower realized densities, maintained smaller focal areas, had greater proportions of nomadic individuals, and established stable social hierarchies slower than wild fry in allopatric lab sections, 2) wild fry in sympatry had poorer condition than all other fry groups in lab sections, 3) in sympatry, wild fry were the recipients of the majority of aggressive acts perpetrated by hatchery fry and other wild fry and usually assumed the subordinate positions within the social hierarchy, 4) all fry in the lab showed a high preference for pools with overhead cover and low preference for gravel and fines and run areas, and 5) wild fry in allopatric lab sections were more socially active than hatchery fry while the reverse was observed in the natural streams. Any influences that could be attributed to inherent differences between stock origins were probably masked by size differences between fry types. The study would have been more complete had I included sympatric lab sections where wild fry emerged first and where fry types emerged simultaneously, and sympatric reaches in natural streams. Results were further confounded by the limited number of wild adults used for broodstock in the lab segment of this study. Progeny produced from so few adults (5 adults of each sex each year) would have very limited genotypic variation compared to what occurs in natural streams. This may partially explain why some findings from lab sections and natural stream reaches differed. Likewise, genotypic expression among wild fry in lab sections may have varied greatly between years. This could explain differences found between years in behavior of wild fry in similar lab treatments. Although this study does not simulate all possible scenarios, results support suspicions that introductions of hatchery fry of larger size and earlier emergence into streams containing wild stocks could disrupt the social structure and negatively influence the realized densities, spatial distribution, growth, and behavior of wild juveniles in recipient streams.
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4703. [Article] Effects of a Wind Energy Development on Greater Sage-Grouse Habitat Selection and Population Demographics in Southeastern Wyoming
Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The ...Citation Citation
- Title:
- Effects of a Wind Energy Development on Greater Sage-Grouse Habitat Selection and Population Demographics in Southeastern Wyoming
- Author:
- LeBeau, Chad W.
Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The University of Wyoming joined this collaborative effort in January 2010, and the National Wind Coordinating Collaborative joined the effort in March 2011. The overall goal of the research was to establish the population-level effects of wind energy development on female sage-grouse seasonal habitat selection and demography. This study represents the only situation in the US where the responses of greater sage-grouse to the infrastructure associated with a wind energy development has been investigated. Our primary objective was to discern the relationship between sage-grouse nest, brood-rearing, and summer habitat selection patterns and survival parameters and the infrastructure of an existing wind energy facility. The Seven Mile Hill (SMH) study area was located north of Interstate 80 and south of the Shirley Basin in Carbon County, Wyoming, US. A control and treatment area was included in the SMH study area, with boundaries of each of these areas determined from lek locations and radio-marked female sage-grouse distributions. The Seven Mile Hill Wind Energy Facility (SWEF; located in the treatment area) consisted of 79 General Electric 1.5-MW wind turbines and approximately 29 km of access roads. The facility became fully operational in December 2008. In addition to the SWEF, other anthropogenic features present in this portion of the study area included approximately eight km of paved roads and 26 km of overhead transmission lines. The control study area had no wind turbines and was adjacent to the SWEF and south of US Highway 30/287. There were approximately 50 km of paved roads and 17 km of overhead transmission lines in this area. The treatment area had four leks that had an average distance of 1.93 km from the nearest SWEF turbines (range = 0.53 to 4.15 km), while the control group consisted of 6 leks with an average distance of 10.99 km from the nearest SWEF turbine (range = 7.09 to 16.16 km). We captured and radio-equipped 346 (160 treatment; 186 control) female sage-grouse within an area consisting of a wind energy development and a control area absent of wind energy development in southeastern Wyoming from 2009–2014. We relocated each radio-marked female approximately twice a week during the nesting, brood rearing, and summer periods. We developed a suite of anthropogenic, vegetation, and environmental covariates to estimate habitat selection and survival for all sage-grouse during the nesting, brood rearing, and summer periods. We used a discrete choice habitat selection model to estimate the relative probability of sage-grouse nest site, brood-rearing, and summer habitat selection within both the control and treatment areas during the post-development period. We did not detect a negative impact of the wind energy facility on nest site selection during the study period. Sage-grouse rearing broods generally avoided suitable brood-rearing habitat near anthropogenic infrastructure that includes wind energy development, major paved roads and transmission lines. Although avoidance was consistent across the years of our study, avoidance of wind turbines was more pronounced in 2012-2014 compared to 2009-2011, suggesting a lag period in the ultimate population-level response to the development of a wind energy facility. Although distance to turbine was not strongly associated with summer habitat selection, the percentage of disturbance associated with wind energy infrastructure did appear to influence summer habitat selection. In addition, we estimated survival during each seasonal period to estimate the effect of the SWEF on population fitness. The SWEF did not have a negative effect on sage-grouse nest survival within the study area over the six-year period, and nest survival did not differ between nests of females captured at treatment and control area leks over the study period. The SWEF did not have a negative effect on sage-grouse brood survival within the study area over the six-year period. Survival was related to habitat features and anthropogenic features that have existed on the landscape for >10 years. Lastly, the SWEF did not have a negative effect on female sage-grouse summer survival within the study area over the six-year period. After controlling for annual and natural variability, we observed a positive effect of the SWEF on female survival when the percentage of disturbance within 0.81 km of a sage-grouse location increased from 0% to 3%. Our study is the first to estimate the impacts of wind energy development on sage-grouse habitat selection and fitness parameters. Female sage-grouse selection of seasonal habitats was variable relative to the infrastructure associated with wind energy facility, but fitness parameters did not appear to be influenced to a great degree by the infrastructure. This pattern of effect is similar to greater prairie-chicken response to a wind energy facility in Kansas but opposite of sage-grouse response to oil and gas development. Ideally, we would have preconstruction data to identify changes in the population and decipher mechanisms in sage-grouse response to infrastructure; however, we are confident that if such impacts to habitat selection and survival did occur then we would have been able to detect these changes over the 6-year study period. The lack of other studies investigating impacts from wind energy development to sage-grouse habitat selection and survival limits our ability to make inferences about the cumulative impacts of wind energy development on sage-grouse, but we were able to describe some of the impacts that wind energy developments may have on sage-grouse populations. Although we attempted to account for possible confounding factors, there is the chance that we did not detect important interactions between environmental features and habitat selection and survival patterns. Future wind energy developments should consider the potential impacts of wind energy development on sage-grouse habitat selection patterns and survival parameters. We recommend facilities similar in size that occupy similar habitats as our study be placed 1.20 km from any occupied sage-grouse nesting, brood-rearing, or summer habitats. We recommend that future research consider predator-prey mechanisms by estimating both avian and mammalian predator densities to better understand the impacts of wind energy development on sage-grouse fitness parameters and to develop appropriate mitigation measures.
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4705. [Article] Linkages among land use, riparian zones, and uptake and transformation of nitrate in stream ecosystems
Land use alters the physical and biological structure of stream ecosystems and potentially alters their capacity to process nitrogen (N), an essential nutrient that has nearly doubled in abundance on the ...Citation Citation
- Title:
- Linkages among land use, riparian zones, and uptake and transformation of nitrate in stream ecosystems
- Author:
- Sobota, Daniel J.
Land use alters the physical and biological structure of stream ecosystems and potentially alters their capacity to process nitrogen (N), an essential nutrient that has nearly doubled in abundance on the biosphere during the past century from human activities. In this dissertation, I quantified uptake and transformation of nitrate (NO₃⁻) in small (≤ third-order) streams and related these dynamics to aquatic ecosystem processes, including primary production and organic matter decomposition, and attributes of riparian zone structure and vegetation composition. I also analyze patterns of stream NO₃⁻ processing among three classes of adjacent land use practices (forest, agriculture, and urban). In Chapter 2, ambient rates of NO₃⁻ uptake and transformation were measured with 24-hr releases of ¹⁵N-labeled NO₃⁻ in nine stream reaches in the Willamette River Basin of western Oregon during summer low flow (July – August). Three reaches each were surrounded by forested, agricultural or urban land use. After standardizing reaches to a 500-m length, I estimated that ≥ 20% of tracer ¹⁵NO₃⁻ was taken up by detrital and autotrophic biomass in eight of the reaches. In the remaining stream, which had the largest discharge (120 L s⁻¹) in this study, only 8% of the tracer was taken up in 500 m. Tracer labeling of detritus and autotrophic biomass and a positive correlation (rs=0.81) of uptake with gross primary production suggested that assimilation was the dominant uptake pathway in all streams. Denitrification, dissimilatory reduction of NO₃⁻ to N₂ and N₂O gases, composed 3 – 15% of ¹⁵N budgets over 500 m in two agricultural reaches and in one urban reach dominated by large slowly-turning over pools. However, denitrification was below detection limit at five of the remaining six reaches. This study showed that pathways of stream NO₃⁻ uptake and transformation differed among streams adjacent to three diverse land use practices. In Chapter 3, I quantified effects of substrate nutritional quality and inorganic N loading (as NO₃⁻) on wood breakdown in western Oregon streams. Short-term (< 2 month) breakdown rates of wood substrates of high nutritional quality (Alnus rubra; red alder) and low quality (Pseudotsuga menziesii; Douglas-fir) increased with dissolved inorganic N (11 to 111 mg N L⁻¹) across six streams (p = 0.04), but this relationship was confounded with concurrent increases in stream temperature. Across the six streams, breakdown rates of red alder were consistently double that of Douglas-fir. A longer-term study (313 d) in a coniferous forest Oregon Cascades stream suggested effects of increased NO₃⁻ availability on wood breakdown became evident after cellulose and lignin components of woody tissues began to decompose (> 4 months of incubation). Average breakdown rates substrates enriched with NO₃⁻ were higher than those incubated in low NO₃⁻ conditions, but this difference was not statistically significant. However, microbial biofilm respiration rates and activity of two enzymes involved in the breakdown of woody tissues (beta-glucosidase and phenol oxidase) on red alder had significantly greater responses to NO₃⁻ additions than on Douglas-fir after four months of incubation in the stream. Results suggest that increases in N loading to streams bordered by riparian forests with fast-growing deciduous species could increase wood breakdown rates. On the other hand, increases to N loading may have a smaller effect on wood breakdown in streams surrounded by long-lived coniferous species. In Chapter 4, I quantified patterns of stream channel and riparian zone attributes for 72 streams equally distributed among forests or grasslands, agriculture, and urban land use practices on from eight major North American regions. I also related these patterns to stream NO₃⁻ uptake determined from ¹⁵NO₃⁻ tracer releases. Agricultural and urban streams had a simplified channel structure (low width-to-depth ratio, low variation in stream depth, and high stream banks) relative to forest or grassland streams. Agricultural and urban streams also had a significantly smaller median sediment diameter (D₅₀) and fraction of benthic sediments composed by silt than in forest and grassland streams. Overstory canopy cover over the channel and in the riparian zone was lowest for agricultural streams but did not significantly differ between forest or grassland streams and urban streams. A multiple regression model showed that stream NO₃⁻ uptake decreased with increasing canopy cover, but also increased with abundance of silt in benthic sediments. This suggested NO₃⁻ uptake was strongly influenced by in-stream primary production and extent of anoxic environments (conducive for denitrification). A multiple regression model for fractional NO₃⁻ uptake by denitrification further supported the concept that extent of anoxic environments influenced overall NO₃⁻ uptake in streams. Through these studies, I demonstrated that attributes of riparian zone structure and vegetation composition can strongly influence NO₃⁻ uptake and transformation in stream ecosystems by controlling organic matter dynamics. I also have shown that riparian zone attributes vary significantly among three different land use types (forest or grassland, agriculture, and urban). Similarly, pathways of NO₃⁻ uptake and effects of NO₃⁻ on wood breakdown did or were expected to differ among different land use types / riparian zone characteristics. However, other factors besides riparian attributes, particularly level of nutrient loading, alteration of stream channel physical structure, and basin position of the stream, must be considered in concert when evaluating effects of land use on riparian zone and stream ecosystem structure and function.
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4706. [Article] All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins
The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat ...Citation Citation
- Title:
- All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins
- Author:
- Hamner, Rebecca Marie
The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat is fisheries-related mortality. The Maui's dolphin is among the most critically endangered cetaceans in the world, with its remnant population primarily concentrated in approximately 140 km along the central west coast of New Zealand's North Island. Its closely related sister subspecies, the Hector's dolphin, is more abundant and offers a useful comparison for studying the Maui's dolphin. My work used genetic tools to examine demographic and genetic parameters relevant for conservation considerations regarding Maui's and Hector's dolphins, as well as to build upon past genetic baselines for the purpose of long-term genetic monitoring of these subspecies. Three genetic datasets formed the basis for most analyses: (1) Maui's 01-07, including 54 Maui's dolphin individuals sampled between 2001 and 2007 (n = 70 biopsies, 12 beachcast); (2) Maui's 10-11, including 40 Maui's dolphin individuals sampled in 2010 and 2011 (n = 69 biopsies, 1 beachcast); and (3) Hector's CB11-12, including 148 Hector's dolphin individuals sampled in Cloudy Bay in 2011 and 2012 (n = 263 biopsies). Microsatellite genotypes were used to identify individuals for a genotype recapture abundance estimate of individuals age 1⁺ (N₁₊) and for the estimation of effective population size (N[subscript e]). Both populations exhibited a high N[subscript e] relative to N₁₊, consistent with expectations given their life history characteristics and the limited data available for other dolphin species. The abundance of Maui's dolphins was confirmed to be very low, Maui's 10-11 N₁₊ = 55 (95% CL = 48 - 69), and as expected, it had much lower linkage disequilibrium N[subscript e] (61, 95% CL = 29 - 338) than Hector's CB11-12 (N[subscript e] = 207, 95% CL = 127 - 447; N₁₊ = 272, 95% CL = 236 - 323). The slightly higher Ne/N₁₊ ratio of the Maui's dolphin compared to the Hector's dolphin is consistent with a recent decline in the Maui's dolphin. Although the point estimates of both N[subscript e] and N₁₊ decreased between the two Maui's dolphin datasets (Maui's 01-07: N[subscript e] = 74, 95% CL = 37 - 318; N₁₊ = 69, 95% CL = 38 - 125), the confidence intervals widely overlapped. Maui's 10-11 had significantly fewer alleles (average 4 alleles/locus) and lower heterozygosity (H₀ = 0.316, H[subscript e] = 0.319) than Hector's CB11-12 (average 7 alleles/locus, H₀ = 0.500, H[subscript e] = 0.495; all P <0.001). Interestingly, one microsatellite locus (PPHO104) had anomalously high diversity (31 to 63 alleles) in both Hector's and Maui's dolphins and appears to be influenced by diversifying selection. The observed and expected heterozygosity, internal relatedness, and F[subscript IS] of Maui's dolphins all showed patterns consistent with a decline of the subspecies, although none differed significantly over the short time interval between the two datasets collected in 2001-07 and 2010-11. The lack of significant decline in any of the parameters analyzed for Maui's dolphins is not surprising given the low power to detect a low to moderate decline over the short interval (<1 generation) between the two sampling periods. Compared to minimum viable effective population sizes proposed to guide management decisions, the Maui's dolphin has declined below the recommended threshold of N[subscript e] = 50, recently increased to N[subscript e] ≥100, thought to be necessary to avoid inbreeding depression in the short term (5 generations, ~65.2 years for Maui's and Hector's dolphins). Additionally, both the Maui's dolphin and Cloudy Bay Hector's dolphin populations are below the recommended threshold of N[subscript e] = 500, recently increased to N[subscript e] ≥1000, thought to be necessary to preserve long-term evolutionary potential. This is less of a concern for the Cloudy Bay Hector's population, which is thought to maintain gene flow with neighboring populations. However, for the small, isolated Maui's dolphin population, inbreeding depression is likely to be an increasing concern. Furthermore, each Maui's dolphin individual holds a disproportionate amount of the total genetic variation of the subspecies and would represent a disproportionately large demographic and genetic loss if it died before realizing its reproductive potential in the population. There is, however, potential for genetic restoration by interbreeding with Hector's dolphins, as genetic monitoring of Maui's dolphins revealed the first contemporary dispersal of four (two living females, one dead female, one dead male) Hector's dolphins into the Maui's dolphin distribution. Two Hector's dolphins (one dead female neonate, one living male) were also sampled along the North Island's southwest coast, outside the presumed range of either subspecies. Together, these records provide evidence of long-distance dispersal by Hector's dolphins (≥400 km) and the possibility of an unsampled Hector's dolphin population along the southwest coast of the North Island or northern South Island. These results highlight the value of genetic monitoring for subspecies lacking distinctive physical appearances, as such discoveries are not detected by other means but have important conservation implications. Although the Maui's dolphin is critically endangered, it is not necessarily doomed to extinction. The subspecies appears to be maintaining an equal sex ratio and connectivity within its remnant range, and the highly diverse locus PPHO104 could potentially offer clues to an inbreeding avoidance mechanism. If Maui's dolphins interbreed with the recently identified Hector's dolphin immigrants, it could provide genetic restoration, enhancing chances of long-term survival of the Maui's dolphin. Continued genetic monitoring and examination of recovered carcasses for phenotypic signs of inbreeding are important for gauging genetic threats to the survival of Maui's dolphins, as well as determining if any Hector's dolphin populations appear to be declining toward the critically endangered state of the Maui's dolphin. The results of this work contributed to the decision by the New Zealand Department of Conservation and Ministry for Primary Industries to conduct an updated risk assessment for Maui's dolphins and accelerate the review of the Maui's Dolphin Threat Management Plan. Consequently, commercial and recreational set net restrictions were extended slightly to reduce entanglement risk to Maui's dolphins utilizing the southern part of their distribution, as well as any Hector's dolphins that disperse north into that area. The results related to the population of Hector's dolphins in Cloudy Bay provide information that will contribute to the upcoming review of the Hector's dolphin component of the Threat Management Plan.
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4707. [Article] Status and Distribution of Native Fishes in the Goose Lake Basin Information Reports number 2008-02
Abstract -- This study describes the current distribution of the nine native fish species in the Oregon portion of the Goose Lake basin (Lake County): Goose Lake redband trout Oncorhynchus mykiss ssp., ...Citation Citation
- Title:
- Status and Distribution of Native Fishes in the Goose Lake Basin Information Reports number 2008-02
Abstract -- This study describes the current distribution of the nine native fish species in the Oregon portion of the Goose Lake basin (Lake County): Goose Lake redband trout Oncorhynchus mykiss ssp., Goose Lake lamprey Entosphenus sp., Goose Lake tui chub Siphateles bicolor thalassinus, Goose Lake sucker Catostomus occidentalis lacusanserinus, Modoc sucker Catostomus microps, Pit-Klamath brook lamprey Entosphenus lethophagus, speckled dace Rhinichthys osculus, Pit roach Lavinia symmetricus mitrulus, and Pit sculpin Cottus pitensis. The Goose Lake basin is an endorheic, or topographically closed basin located in south central Oregon and northeastern California. The basin is within the usually closed northeastern extremity of the adjoining Sacramento River basin, astride the Oregon-California boundary. Although most of the lake lies in California, most of its valley and nearly two-thirds of the total drainage area (~722 sq. mi.) are in Oregon. The largest streams in the basin are Drews, Cottonwood, and Thomas Creeks. Annual precipitation averages about 36 cm per year (Phillips and van Denburgh 1971). Goose Lake overflowed briefly into the North Fork Pit River in 1868 and 1881, but storage and diversion of irrigation water has substantially reduced the inflow and future overflow is unlikely (USGS 1971). The lakebed was dry in the summers of 1926, 1929- 1934, and 1992. About half the basin is forestland, 20% is hay fields and pastureland, and 16% is shrub and rangeland. Currently, almost 35% of the inflow is diverted for irrigation (OWRD 1989). The Goose Lake basin is home to four endemic fish taxa: the Goose Lake redband trout, lamprey, sucker, and tui chub. Endemic fishes of the Goose Lake basin split their life histories between Goose Lake and its tributaries, as opposed to the five native but non-endemic species that primarily occupy stream habitats. Pit roach and all endemic fishes except Goose Lake tui chub are listed as a “species of concern” by the USFWS, a designation that implies there is concern about species viability, but not enough information is known to initiate a listing review for threatened or endangered status. The Modoc sucker was listed as a federally endangered species in 1985 (USFWS 1985). No formal recovery plan was required due to an existing “Action Plan for the Recovery of the Modoc Sucker” (USFWS 1984). Most of the recovery actions outlined in the action plan were either completed or are no longer relevant (Stewart Reid, Western Fishes, personal communication). However, actions 26 and 27 pertaining to range expansion remain incomplete. Action 26 suggests reclassification to threatened upon establishment of safe populations (for 3-5 years) throughout the Rush and Turner Creek watersheds in the Pit River basin. Action 27 suggests delisting upon establishing safe populations in two other historic streams. At the time of listing, the historic range of Modoc sucker was thought to have included only two small tributaries of the Pit River in Modoc and Lassen Counties, Ash and Turner Creeks (USFWS 1985). Therefore, a major recovery goal was to expand the species’ range with additional populations (USFWS 1984). In 2001, reexamination of historical documents and museum specimens established that Modoc suckers had also historically occupied Thomas Creek in the Goose Lake basin. Field collections in 2001, with subsequent morphological and genetic analysis, confirmed that the population was still present in Thomas Creek (Stewart Reid, Western Fishes, personal communication); however, the broader range of Modoc sucker in the Goose Lake watershed was not known. In 1995, the Goose Lake Fishes Working Group drafted a conservation plan for “prelisting” recovery of all native fish in response to severe drought and habitat degradation (GLFWG 1995). The Aquatic Inventories Project of the Oregon Department of Fish and Wildlife (ODFW) conducted habitat and fish distribution surveys (1991-1995) to obtain baseline information to help inform recovery efforts (ODFW, unpublished data). Since then, field work to monitor the distribution and abundance of Goose Lake fishes has been limited and sporadic, targeting only Goose Lake redband trout and Modoc sucker (Dambacher 2001; Reid 2007). No comprehensive follow up work has been conducted to evaluate fish response to climatic conditions, habitat restoration projects, and continued irrigation activities. ODFW recently drafted a status review of native fish of Oregon (ODFW 2005). Except for redband trout, Goose Lake fishes were not included in the status review due to a lack of new information since the previous status review in 1995 (Kostow et al. 1995). Further, the review of Goose Lake redband trout was limited by a lack of long-term data series. The first objective of this study was to document the current distribution of native fishes in Oregon’s portion of the Goose Lake basin and assess changes in distribution that may have occurred since the last surveys were conducted 12 years ago. The second objective was to provide new information about the distribution of Modoc suckers within the basin. The third objective was to determine relative abundance and age-class diversity of native fishes at randomly selected sample sites. All objectives were addressed throughout the potential riverine distribution of fish in the Oregon portion of the Goose Lake basin. Information gathered in this study is critical to effective conservation and management of each species and its habitat. In addition, this report describes the distribution and relative abundance of nonnative fishes (fathead minnow (Pimephales promelas), brown bullhead (Ameiurus nebulosus), white crappie (Pomoxis annularis), yellow perch (Perca flavescens), pumpkinseed (Lepomis gibbosus), and brook trout (Salvelinus fontinalis)) in the basin. Unlike prior efforts, this study used a statisticallybased design to select sample points with the aim of achieving a representative sample across the Oregon portion of the Goose Lake watershed. Additionally, a wide array of fish sampling gear was employed to maximize our ability to capture all fish species present across the diversity of habitat types encountered.
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4708. [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
- 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.
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4709. [Article] 2006 Oregon Chub Investigations Progress Reports 2006
Abstract -- Oregon chub Oregonichthys crameri, small minnows endemic to the Willamette Valley, were federally listed as endangered under the Endangered Species Act in 1993. Factors implicated in the decline ...Citation Citation
- Title:
- 2006 Oregon Chub Investigations Progress Reports 2006
Abstract -- Oregon chub Oregonichthys crameri, small minnows endemic to the Willamette Valley, were federally listed as endangered under the Endangered Species Act in 1993. Factors implicated in the decline of this species include changes in flow regimes and habitat characteristics resulting from the construction of flood control dams, revetments, channelization, diking, and the drainage of wetlands. The Oregon chub is further threatened by predation and competition by non-native species such as largemouth bass Micropterus salmoides, crappies Pomoxis sp., sunfishes Lepomis sp., bullheads Ameiurus sp., and western mosquitofish Gambusia affinis. We continued surveys initiated in 1991 in the Willamette River drainage to quantify the abundance of known Oregon chub populations, search for unknown populations, evaluate potential introduction sites, and monitor introduced populations as part of the implementation of the Oregon Chub Recovery Plan. We sampled a total of 103 sites in 2006. No new populations of Oregon chub were discovered. Thirty-five of the 103 sites were new locations that were sampled for the first time in 2006. Sixty-eight sites, sampled on at least one occasion between 1991-2005, were revisited. We confirmed the continued existence of Oregon chub at 33 locations. These included 23 naturally occurring and 10 introduced populations. Locations of naturally occurring populations were: Santiam drainage (Geren Island, Santiam I-5 Side Channels, Santiam Conservation Easement, Stayton Public Works Pond, Green’s Bridge Backwater, Pioneer Park, Santiam Conservation Easement, and Gray Slough), Mid-Willamette drainage (Finley Gray Creek Swamp), McKenzie drainage (Shetzline Pond and Big Island), Coast Fork Willamette drainage (Coast Fork Side Channels and Lynx Hollow), and the Middle Fork Willamette drainage (two Dexter Reservoir alcoves, East Fork Minnow Creek Pond, Shady Dell Pond, Buckhead Creek, two Elijah Bristow State Park sloughs and an island pond, Barnhard Slough, and Hospital Pond). Introduced populations were located in the Middle Fork Willamette (Wicopee Pond and Fall Creek Spillway Ponds), Santiam (Foster Pullout Pond), McKenzie (Russell Pond), Coast Fork Willamette (Herman Pond), and Mid-Willamette drainages (Dunn Wetland, Finley Display Pond, Finley Cheadle Pond, Ankeny Willow Marsh, and Jampolsky Wetlands). We did not find Oregon chub at 14 locations where they were collected on at least one occasion between 1991-2005 (Jasper Park Slough, Wallace Slough, East Ferrin Pond, Dexter East Alcove, Hospital Impoundment Pond, Rattlesnake Creek, Elijah Bristow Large Gravel Pit, Elijah Bristow Small Gravel Pit, Little Muddy Creek tributary, Bull Run Creek, Camas Swale, Barnhard Slough, Camous Creek, and Dry Muddy Creek). Nonnative fish were collected at most of these locations. We obtained abundance estimates of naturally occurring populations of Oregon chub at 18 locations in the Middle Fork Willamette (East Fork Minnow Creek Pond, Shady Dell Pond, Elijah Bristow State Park Sloughs and Island Pond, Hospital Pond, Dexter Reservoir Alcoves, Haws Pond, and Buckhead Creek), Santiam (Geren Island, Gray Slough, Stayton Public Works Pond, Pioneer Park Pond, and Santiam I-5 Side Channels), McKenzie (Big Island and Shetzline Pond), and Mid-Willamette drainages (Finley Gray Creek) (Table 1). We obtained abundance estimates for 10 introduced populations of Oregon chub, located in Fall Creek Spillway Ponds, Wicopee Pond, Dunn Wetland Ponds, Finley Display Pond, Finley Cheadle Pond, Ankeny Willow Marsh, Jampolsky Wetlands, Foster Pullout Pond, Herman Pond, and Russell Pond. The three largest populations in 2006 were introduced populations. In addition, we evaluated eleven potential Oregon chub introduction sites in the Willamette River drainage. We introduced Oregon chub into the South Stayton Pond, a recently restored site located on ODFW property in the Santiam drainage, from Stayton Public Works Pond and Pioneer Park Pond. The Oregon Chub Recovery Plan (U.S. Fish and Wildlife Service 1998) set recovery criteria for downlisting the species to “threatened” and for delisting the species. The criteria for downlisting the species are: 1) establish and manage 10 populations of at least 500 adult fish, 2) all of these populations must exhibit a stable or increasing trend for five years, and 3) at least three populations meeting criterion 1 and 2 must be located in each of the three recovery areas (Middle Fork Willamette River, Santiam River, and Mid-Willamette River tributaries). In 2006, there were 18 populations totaling 500 or more individuals (Table 1). Thirteen of these populations also met the second criteria. Of the 13 populations meeting criteria 1 and 2, eight were located in the Middle Fork Willamette drainage, three were located in the Mid-Willamette drainage, and two were located in the Santiam drainage. With the addition of one more stable population in the Santiam drainage, the downlisting criteria will be met. Findings to date indicate that Oregon chub remain at risk due to the loss of suitable habitat and the continued threats posed by the proliferation of non-native fishes, illegal water withdrawals, accelerated sedimentation, and potential chemical spills or careless pesticide applications. Their status has improved in recent years, resulting primarily from successful introductions and the discovery of previously undocumented populations.
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This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/nature/index.html. To ...
Citation Citation
- Title:
- Averting biodiversity collapse in tropical forest protected areas
- Author:
- Lovett, Jon, Arroyo-Rodriguez, Victor, Ewango, Corneille, Rendeiro, Julio, Dirzo, Rodolfo, Poulsen, John, Corlett, Richard, Waltert, Matthias, Cords, Marina, Goodale, Uromi, Struhsaker, Thomas, Terborgh, John, Magnusson, William, Schaab, Gertrud, Banki, Olaf, Babweteera, Fred, Foster, Mercedes, Rainey, Hugo, De Dijn, Bart, Herbinger, Ilka, Janovec, John, Montag, Luciano, Stanford, Craig, Lugo, Ariel, Guix, Juan C., Sun, I. Fang, Cannon, Charles H., Silman, Miles R., Kasangaki, Aventino, Wang, Benjamin, Surbeck, Martin, Bunyavejchewin, Sarayudh, Maisels, Fiona, Lindsell, Jeremy, Nielsen, Martin R., Krishnaswamy, Jagdish, Savini, Tommaso, Parthasarathy, N., Auzel, Philippe, Killeen, Timothy, de Almeida, Samuel Soares, Abernethy, Kate, Benitez-Malvido, Julieta, de Castilho, Carolina Volkmer, Venn, Linda, Umapathy, Govindaswamy, Carroll, Richard, Pisciotta, Katia, Arias-G, Juan Carlos, Wright, Patricia, Baker, Patrick, Jin, Chen, Round, Philip, Bruehl, Carsten A., Linsenmair, K. Eduard, McNab, Roan, Huang, Zhongliang, Itoh, Akira, Scatena, Frederick, Sloan, Sean P., Schulze, Christian, Klop, Erik, McGraw, W. Scott, Pearson, Richard, Laval, Richard, Karpanty, Sarah, Sanaiotti, Tania, Roedel, Mark-Oliver, Ickes, Kalan, Ashton, Peter, Diesmos, Arvin, Guthiga, Paul, Coates, Rosamond, Nepal, Sanjay, Kone, Inza, Plumptre, Andrew, Williams, Stephen, Goodman, Steven, van der Ploeg, Jan, Pitman, Nigel, Lattke, John, Mack, Andrew L., Brockelman, Warren, Haber, William, Wright, Debra D., Clark, Connie J., Chellam, Ravi, Smith, Thomas B., Zamzani, Franky, Reynolds, Glen, Edwards, David, Chapman, Colin, Quesada, Mauricio, Knott, Cheryl, Rajathurai, Subaraj, Renton, Katherine, Danielsen, Finn, Jiangming, Mo, Whitney, Ken, Vasudevan, Karthikeyan, Bila-Isia, Inogwabini, Estrada, Alejandro, Ivanauskas, Natalia, Whitacre, David, Timm, Robert, Congdon, Robert, Kalko, Elisabeth, Harris, David, Stewart, Kristine, Xiankai, Lu, Jackes, Betsy, da Silva, Rosa de Nazarepaes, Martins, Marlucia, Kalka, Margareta, Rivera, Jorge Vega, King, Hen-biau, Turkalo, Andrea, Clavijo, Jose, Wilkie, David, Wright, S. Joseph, Cao, Min, Sodhi, Navjot, Janzen, Daniel, Mudappa, Divya, Laurance, Susan G., Stoner, Kathryn E., Rovero, Francesco, McClearn, Deedra, Eaton, Mitchell, Hamer, Keith, Parker, Kenneth, Leal, Miguel, Norconk, Marilyn, Gale, George, Stokes, Emma, Hill, Jane, van Weerd, Merlijn, Logsdon, Willis, Fedigan, Linda, Alvarez, Patricia, Brokaw, Nicholas, Marshall, Andrew R., Dave, Chittaranjan, Seidensticker, John, Edwards, Felicity, Campbell, Mason, Useche, D. Carolina, Feer, Francois, Nabe-Nielsen, Jacob, Di Fiore, Anthony, Ouboter, Paul, Yonzon, Pralad, Watts, David, Laurance, William F., Davies, Glyn, Arroyo, Luzmila, Kudavidanage, Enoka, Blake, Stephen, Hart, John, Verea, Carlos, Tobler, Mathias, Willis, Jacalyn Giacalone, Forget, Pierre-Michel, Lentino, Miguel, Lawton, Robert, Roetgers, Christiane, Blom, Allard, Robinson, Douglas, Opiang, Muse, Tscharntke, Teja, Ribeiro, Jose Lahoz da Silva, Thompson, Jo Myers, Losos, Elizabeth, Babaasa, Dennis, Rothman, Jessica, Chao, Jung-Tai, Doran-Sheehy, Diane, Dinerstein, Eric, Harrison, Rhett, Ling-Ling, Lee, O'Donnell, Sean, Donnelly, Maureen A., Reichard, Ulrich, Leonel, Cristiane, Leighton, Mark, Bobo, Kadiri S., Kress, W. John, Fruth, Barbara, Pringle, Catherine, Thomas, Duncan, Justiniano, Hermes, Farwig, Nina, Bradshaw, Corey J. A., Sukumar, Raman, Venkataraman, Meena, Lwanga, Jeremiah, Ashton, Mark, Reynolds, Vernon, Sheil, Douglas, Riley, Erin, Siaka, Alhaji, Nakagawa, Michiko, Fashing, Peter, Urbina-Cardona, J. Nicolas, Beisiegel, Beatriz de Mello, Emmons, Louise, Weber, William, West, Paige, Reinartz, Gay, Dattaraja, H. S., Chave, Jerome, Prawiradilaga, Dewi, Jones, Trevor, Sakai, Shoko, Bass, Margot, Novotny, Vojtech
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