A Multi-Spatial Scale Economic Analysis of the Impacts of Bear Damage to Douglas-fir on Private Timberlands in the Pacific Northwest

Black bears (Ursus americanus) in western Oregon and Washington peel bark from conifers in early spring to forage on the sugar-rich phloem and cambial tissues. This provides important energy at a time when similarly attractive forage is scarce. Bears often damage Douglas-fir (Pseudotsuga menziesii) trees in stands that are intensively managed for timber production, as management activities including thinning and fertilization increase productivity. Fully girdled trees result in a complete economic loss while partial girdling reduces survival rates as well as merchantable volume. Previous studies on economic impacts have assessed only those losses to fully girdled trees, but not additional impacts from wounded trees. We surveyed four severely damaged stands to assess economic impacts at the stand-level, and surveyed 122 randomly selected vulnerable stands to assess economic impacts at the landscape-level. Two damage scenarios were considered. Scenario one accounted for the additional mortality and volume losses from partially girdled trees, whereas scenario two assumed that all bear-peeled trees resulted in a complete loss. Stand volumes were estimated using the Forest Vegetation Simulator growth and yield model. Economic losses were estimated using the Fuel Reduction Cost Simulator and present value models. At the stand-level, economic losses to severe bear damage in scenario one ranged from $6,100 to$24,500. Economic losses in scenario two ranged from $19,500 to$74,700. Undamaged stands were valued from $43K-$250K. At the landscape level, economic losses to vulnerable stands in scenario one ranged from $44,500 to$726,000. Economic losses in scenario two ranged from $169,000 to$2.8M. Undamaged stands were valued from $48M-$780.5M. Root disease was a more prevalent damage agent than black bear damage. The majority of bear damage observed (92%) was older (>2 yrs) and existed at a low frequency (1.5 bear damaged trees/ha) and severity across the landscape. Our results suggest that bear damage management over the last two decades may have reached a level of efficiency at reducing damage, and if continued, bear damage may remain at low levels across the landscape. On-the-ground monitoring of the status of bear damage frequency and severity across western Oregon and Washington at both the stand and landscape levels will provide an understanding of these changes over time as a result of management decisions

Estimating stand-level economic impacts of black bear damage to intensively managed forests

Black bears (Ursus americanus Pallas, 1780) peel conifers in early spring to forage on energy-rich vascular tissues, resulting in damage to timber stands. The objective of our study was to develop and demonstrate a conceptual framework and methods for estimating stand-level volume and economic losses from black bear damage. We created tree lists from surveys of healthy and bear-damaged trees in timber stands of western Washington and Oregon. The forest growth model Forest Vegetation Simulator (FVS) was used to project stand volume under two damage scenarios and an undamaged scenario. One damage scenario (salvage) accounted for mortality and volume losses of fully and partially girdled trees; a second scenario (total loss) assumed complete loss of all trees peeled by black bears, regardless of peeling severity. The Fuel Reduction Cost Simulator (FRCS) was applied to estimate the value of logs delivered to the mill after accounting for logging and hauling costs associated with harvest. Present value of stands was calculated to translate volume losses into economic losses associated with bear damage. Economic losses ranged from 4% to 16% (salvage) and from 17% to 46% (total loss) of net present value. Our approach can be adapted for other forest settings and for forest management plans that assess wildlife damage. L’ours noir (Ursus americanus Pallas, 1780) arrache l’écorce des conifères tôt au printemps pour se nourrir des tissus vasculaires riches en énergie et cause des dommages aux peuplements forestiers. L’objectif de notre étude consistait à élaborer et présenter un cadre conceptuel et des méthodes pour estimer à l’échelle du peuplement les pertes de volume ainsi que financières dues aux dommages causés par l’ours noir. Nous avons créé des listes d’arbres sains et d’arbres endommagés par les ours à partir des inventaires de peuplements forestiers de l’ouest des États de Washington et de l’Oregon. Un modèle de croissance de la forêt, le simulateur de végétation forestière, a été utilisé pour prévoir le volume d’un peuplement selon deux scénarios comportant des dommages et un troisième qui n’en comporte pas. Un scénario comportant des dommages (récupération) tenait compte de la mortalité et des pertes de volume des arbres partiellement et complètement annelés; un second scénario (perte totale) assumait la perte complète de tous les arbres endommagés par les ours noirs, peu importe la sévérité des dommages. Le simulateur du coût de réduction des combustibles a été appliqué pour estimer la valeur des billes livrées à l’usine après avoir pris en compte les coûts de la coupe et du débardage associés à la récolte. La valeur actualisée des peuplements a été calculée pour traduire les pertes de volume en pertes financières associées aux dommages causés par les ours. Les pertes financières variaient de 4–16 % (récupération) et de 17–46 % (perte totale) de la valeur actualisée nette. Notre approche peut être adaptée à d’autres situations ainsi qu’aux plans d’aménagement forestier qui évaluent les dommages causés par la faune

Estimating economic impact of black bear damage to western conifers at a landscape scale

Black bear (Ursus americanus) damage to trees in the Pacific Northwest is common, although volume and economic losses are unknown. Common measures to quantify bear damage to conifers at large scales rely solely on aerial estimates of red tree crowns (caused by complete girdling) and broad assumptions about stand characteristics. We surveyed 122 vulnerable stands in the Coast Range and western Cascades of Oregon using both aerial surveys and ground surveys. Then, we modeled 4 damage scenarios (Salvage; Total Loss; Root Disease; and Combined Damage) with the Forest Vegetation Simulator (FVS) growth and yield model and the Fuel Reduction Cost Simulator (FRCS). Damage polygons, digitized in real time from aerial surveys identifying red (dead or dying) tree crowns, overestimated bear damage by approximately 5-fold due to misclassification with root disease, and failed to detect partially peeled trees that contributed to economic loss. Damage polygons assessed from the air generally did not include red crowns, and were a mean distance of 58.8m (SE=8.8) from damage polygons’ outer edges to the nearest red crown. We accounted for mortality and volume losses from partially girdled trees that did not show red crowns in our Salvage scenario, whereas we assumed that all bear-peeled trees resulted in complete loss in the Total Loss scenario. At the landscape scale, economic loss was ≤0.35% of net present value under both damage scenarios, while processing bear damage trees (Salvage) was the most efficacious option. At the landscape scale, our worst-case scenario (Total Loss) resulted in an estimated loss of $56/ha to bear damage, 10-fold less than a previously reported estimate of$585/ha. Root disease was a more prevalent damage agent than bear damage but did not affect net present value at harvest. The majority (92%) of bear damage observed in ground surveys was older (\u3e 2 yrs) and existed at a low frequency (1.5 bear damaged trees/ha) and severity across the landscape. Our results suggest that black bear damage is not uniformly distributed and that perceived impact varies with spatial scale. On-the-ground monitoring of the status of bear damage across the western Oregon landscape will identify hot spots of severe peeling and provide an understanding of these changes over time

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

Estimating stand-level economic impacts of black bear damage to intensively managed forests

Black bears (Ursus americanus Pallas, 1780) peel conifers in early spring to forage on energy-rich vascular tissues, resulting in damage to timber stands. The objective of our study was to develop and demonstrate a conceptual framework and methods for estimating stand-level volume and economic losses from black bear damage. We created tree lists from surveys of healthy and bear-damaged trees in timber stands of western Washington and Oregon. The forest growth model Forest Vegetation Simulator (FVS) was used to project stand volume under two damage scenarios and an undamaged scenario. One damage scenario (salvage) accounted for mortality and volume losses of fully and partially girdled trees; a second scenario (total loss) assumed complete loss of all trees peeled by black bears, regardless of peeling severity. The Fuel Reduction Cost Simulator (FRCS) was applied to estimate the value of logs delivered to the mill after accounting for logging and hauling costs associated with harvest. Present value of stands was calculated to translate volume losses into economic losses associated with bear damage. Economic losses ranged from 4% to 16% (salvage) and from 17% to 46% (total loss) of net present value. Our approach can be adapted for other forest settings and for forest management plans that assess wildlife damage. L’ours noir (Ursus americanus Pallas, 1780) arrache l’écorce des conifères tôt au printemps pour se nourrir des tissus vasculaires riches en énergie et cause des dommages aux peuplements forestiers. L’objectif de notre étude consistait à élaborer et présenter un cadre conceptuel et des méthodes pour estimer à l’échelle du peuplement les pertes de volume ainsi que financières dues aux dommages causés par l’ours noir. Nous avons créé des listes d’arbres sains et d’arbres endommagés par les ours à partir des inventaires de peuplements forestiers de l’ouest des États de Washington et de l’Oregon. Un modèle de croissance de la forêt, le simulateur de végétation forestière, a été utilisé pour prévoir le volume d’un peuplement selon deux scénarios comportant des dommages et un troisième qui n’en comporte pas. Un scénario comportant des dommages (récupération) tenait compte de la mortalité et des pertes de volume des arbres partiellement et complètement annelés; un second scénario (perte totale) assumait la perte complète de tous les arbres endommagés par les ours noirs, peu importe la sévérité des dommages. Le simulateur du coût de réduction des combustibles a été appliqué pour estimer la valeur des billes livrées à l’usine après avoir pris en compte les coûts de la coupe et du débardage associés à la récolte. La valeur actualisée des peuplements a été calculée pour traduire les pertes de volume en pertes financières associées aux dommages causés par les ours. Les pertes financières variaient de 4–16 % (récupération) et de 17–46 % (perte totale) de la valeur actualisée nette. Notre approche peut être adaptée à d’autres situations ainsi qu’aux plans d’aménagement forestier qui évaluent les dommages causés par la faune

Estimating economic impact of black bear damage to western conifers at a landscape scale

Black bear (Ursus americanus) damage to trees in the Pacific Northwest is common, although volume and economic losses are unknown. Common measures to quantify bear damage to conifers at large scales rely solely on aerial estimates of red tree crowns (caused by complete girdling) and broad assumptions about stand characteristics. We surveyed 122 vulnerable stands in the Coast Range and western Cascades of Oregon using both aerial surveys and ground surveys. Then, we modeled 4 damage scenarios (Salvage; Total Loss; Root Disease; and Combined Damage) with the Forest Vegetation Simulator (FVS) growth and yield model and the Fuel Reduction Cost Simulator (FRCS). Damage polygons, digitized in real time from aerial surveys identifying red (dead or dying) tree crowns, overestimated bear damage by approximately 5-fold due to misclassification with root disease, and failed to detect partially peeled trees that contributed to economic loss. Damage polygons assessed from the air generally did not include red crowns, and were a mean distance of 58.8m (SE=8.8) from damage polygons’ outer edges to the nearest red crown. We accounted for mortality and volume losses from partially girdled trees that did not show red crowns in our Salvage scenario, whereas we assumed that all bear-peeled trees resulted in complete loss in the Total Loss scenario. At the landscape scale, economic loss was ≤0.35% of net present value under both damage scenarios, while processing bear damage trees (Salvage) was the most efficacious option. At the landscape scale, our worst-case scenario (Total Loss) resulted in an estimated loss of $56/ha to bear damage, 10-fold less than a previously reported estimate of$585/ha. Root disease was a more prevalent damage agent than bear damage but did not affect net present value at harvest. The majority (92%) of bear damage observed in ground surveys was older (\u3e 2 yrs) and existed at a low frequency (1.5 bear damaged trees/ha) and severity across the landscape. Our results suggest that black bear damage is not uniformly distributed and that perceived impact varies with spatial scale. On-the-ground monitoring of the status of bear damage across the western Oregon landscape will identify hot spots of severe peeling and provide an understanding of these changes over time