The influence of an ecosystem engineer on nutrient subsidies and fish invasions in southwestern Montana

Streams and associated riparian zones are among the world\u27s most highly valued yet threatened ecosystems. Interest in using the ecosystem engineering behavior of beaver tomeet watershed conservation goals is becoming more pervasive, owing to substantive work documenting the physical effects of beaver impoundments on freshwater ecosystems. However, it is unclear how beaver modify ecological processes linking abiotic factors to changes in the surrounding biotic community. I investigated how beaver impoundments influence local food web processes, as well as impact native fish species threatened by nonnative invasions. I showed that beaver impoundments enhanced aquatic resource availability to terrestrial consumers. Beaver impounded watersheds had increased densities of emerging aquatic macroinvertebrates and higher levels of aquatic carbon in terrestrial consumer tissues, resulting in higher terrestrial consumer abundances. Beaver impoundments also had measurable effects on invasion dynamics between nonnative brook charr and native cutthroat trout populations. Brook charr are native to the eastern U.S., and are a key factor in native cutthroat declines in western watersheds. Streams with beaver had potential negative impacts for cutthroat, with higher brook charr densities, and increased spatial overlap between these species. In contrast, young-of-theyear cutthroat in invaded streams maintained high growth rates with beaver present, but showed growth reductions without beaver. Thus beaver conveyed both negative and positive impacts to cutthroat trout. At the population level, I found that cutthroat in the non-beaver invaded watershed exhibited low survival rates, negative population growth, and a short median time to extinction. With beaver present in invaded streams, cutthroat exhibited 40 % higher survival rates relative to the non-beaver control. This led to cutthroat population growth rates 5 - 20 % higher than in non-beaver streams, with longer median times to extinction. Therefore, beaver impoundments had positive implications for cutthroat persistence in brook charr invaded streams. My research links the habitat altering effects of beaver to changing ecological processes that influence community and population structure of other elements of the system, with implications for persistence of native species. Understanding the ecosystem effects of a highly interactive species like beaver is crucial to predicting repercussions of using beaver in a restoration context

Habitat Selection by Chiricahua Leopard Frogs During Summer Monsoons

One-third of the described species of amphibians worldwide are threatened with extinction, including the Chiricahua leopard frog (Lithobates chiricahuensis).  This frog is highly aquatic, found in portions of Arizona and New Mexico, and listed as threatened under the Endangered Species Act.  Currently, the Chiricahua leopard frog is restricted to anthropogenic sources of water, including tanks maintained for livestock, throughout most of its range.  Movement habits of this frog and patterns of dispersal between disjunct water sources are not well understood.  We attached radio transmitters to 44 total frogs on the Ladder Ranch in southern New Mexico during summer 2014 and located each frog daily for up to 8 weeks (mean = 29 days).  We quantified habitat characteristics at each frog location and a random location 5 meters away.  We assessed fine-scale habitat selection using conditional logistic regression and also explored the degree of variation in selection among individual frogs.  Frogs chose areas with more low-lying cover (especially aquatic vegetation and woody debris), less overstory cover, and a mud substrate.  Whether the location was far from or close to water and the amount of overstory cover did not appear to be important for selection, suggesting that frogs are able to find areas that provide habitat away from water One-third of the described species of amphibians worldwide are threatened with extinction, including the Chiricahua leopard frog (Lithobates chiricahuensis).  This frog is highly aquatic, found in portions of Arizona and New Mexico, and listed as threatened under the Endangered Species Act.  Currently, the Chiricahua leopard frog is restricted to anthropogenic sources of water, including tanks maintained for livestock, throughout most of its range.  Movement habits of this frog and patterns of dispersal between disjunct water sources are not well understood.  We attached radio transmitters to 44 total frogs on the Ladder Ranch in southern New Mexico during summer 2014 and located each frog daily for up to 8 weeks (mean = 29 days).  We quantified habitat characteristics at each frog location and a random location 5 meters away.  We assessed fine-scale habitat selection using conditional logistic regression and also explored the degree of variation in selection among individual frogs.  Frogs chose areas with more low-lying cover (especially aquatic vegetation and woody debris), less overstory cover, and a mud substrate. Whether the location was far from or close to water and the amount of overstory cover did not appear to be important for selection, suggesting that frogs are able to find areas that provide habitat away from water bodies.  The variation among individuals was low, suggesting that tracked were selecting similar habitat characteristics. The findings of this study will inform active management of amphibians in anthropogenic settings, where managers can enhance amphibian habitat characteristics between occupied sites to improve population connectivity

Understanding Movement Patterns of Chiricahua Leopard Frogs to Promote Species Persistence in Desert Ecosystems

One-third of the described species of amphibians worldwide are threatened with extinction, including the Chiricahua leopard frog (Lithobates chiricahuensis). This frog is highly aquatic, found in portions of Arizona and New Mexico, and listed as threatened under the Endangered Species Act. Currently, habitat for the Chiricahua leopard frog generally is restricted to anthropogenic sources of water, including tanks maintained for livestock. Movement habits of this frog and patterns of dispersal between disjunct water sources are not well understood. On the Ladder Ranch, a working bison ranch in southern New Mexico, we constructed pitfall traps to capture frogs leaving stock tanks. We attached radio transmitters to 14 individuals during the summer of 2013 to study the potential for movement between widely-spaced tanks. Individuals captured in stock tanks (n = 11) showed very high site fidelity, never leaving their source location while carrying transmitters up to 18 days. Individuals captured in a nearby creek (n = 3) moved as much as 2800 m over a 17-day period. Daily movements of these individuals varied greatly (mean = 121 m, SD = 249) and do not appear to be related to temperature or precipitation. During the 2014 field season, we will attempt to track a larger number of animals moving along the creek corridor and to nearby tanks. Quantifying movement abilities of native amphibians will allow biologists to manage anthropogenic water sources to support movement between habitat patches and maintain functioning metapopulations, while preserving important features of the Ranch for livestock use

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Release method evaluation for swift fox reintroduction at Bad River Ranches in South Dakota

Reintroductions have increasingly become effective at restoring populations of imperiled native wildlife. How animals are reintroduced into unfamiliar environments may have pronounced impacts on behavior, survival, and reproduction. We evaluated the influence of four release methods on survival rates of translocated swift foxes at Bad River Ranches (BRR) in western South Dakota: (1) hard-release, (2) short-soft-release, (3) long-soft-release, an

Release Method Evaluation for Swift Fox Reintroduction at Bad River Ranches in South Dakota

Reintroductions have increasingly become effective at restoring populations of imperiled native wildlife. How animals are reintroduced into unfamiliar environments may have pronounced impacts on behavior, survival, and reproduction. We evaluated the influence of four release methods on survival rates of translocated swift foxes at Bad River Ranches (BRR) in western South Dakota: (1) hard-release, (2) short-soft-release, (3) long-soft-release, and (4) captive born. A total of 179 foxes captured in Wyoming during 2002–2007 and in Colorado during 2006–2007 were released into BRR and the surrounding area. In addition, 43 pups born to foxes in the long-soft-release category were also released. All release methods incorporated a 14- to 21-day quarantine period. Hard-release foxes were released directly from a transport kennel, whereas short-soft-release foxes were released from soft-release pens by opening the door and allowing the foxes to leave voluntarily. Long-soft-release foxes were held for more than 250 days on-site in soft-release pens through the winter and released in the following year in early summer. During 2002–2007, survival of reintroduced foxes differed significantly (p \u3c 0.05) by age (adult vs. juvenile), release year, and release method. The short-soft-release method had the highest 60-day post-release survival probability compared with the other release methods. We did not detect any differences in mortality hazards between wild-born and short-soft-release foxes. Reintroduction programs based on short-soft-releases are useful for restoring or augmenting populations to advance the conservation of the swift fox

Regular, sustained-release morphine for chronic breathlessness : A multicentre, double-blind, randomised, placebo-controlled trial

Introduction Morphine may decrease the intensity of chronic breathlessness but data from a large randomised controlled trial (RCT) are lacking. This first, large, parallel-group trial aimed to test the efficacy and safety of regular, low-dose, sustained-release (SR) morphine compared with placebo for chronic breathlessness. Methods Multisite (14 inpatient and outpatient cardiorespiratory and palliative care services in Australia), parallel-arm, double-blind RCT. Adults with chronic breathlessness (modified Medical Research Council≥2) were randomised to 20 mg daily oral SR morphine and laxative (intervention) or placebo and placebo laxative (control) for 7 days. Both groups could take ≤6 doses of 2.5 mg, â € as needed', immediate-release morphine (≤15 mg/24 hours) as required by the ethics review board. The primary endpoint was change from baseline in intensity of breathlessness now (0-100 mm visual analogue scale; two times per day diary) between groups. Secondary endpoints included: worst, best and average breathlessness; unpleasantness of breathlessness now, fatigue; quality of life; function; and harms. Results Analysed by intention-to-treat, 284 participants were randomised to morphine (n=145) or placebo (n=139). There was no difference between arms for the primary endpoint (mean difference -0.15 mm (95% CI -4.59 to 4.29; p=0.95)), nor secondary endpoints. The placebo group used more doses of oral morphine solution during the treatment period (mean 8.7 vs 5.8 doses; p=0.001). The morphine group had more constipation and nausea/vomiting. There were no cases of respiratory depression nor obtundation. Conclusion No differences were observed between arms for breathlessness, but the intervention arm used less rescue immediate-release morphine. Trial registration number ACTRN12609000806268