Effectiveness of Voluntary Conservation Agreements: Case Study of Endangered Whales and Commercial Whale Watching

Abstract: The use of voluntary approaches to achieve conservation goals is becoming increasingly popular. Nevertheless, few researchers have quantitatively evaluated their efficacy. In 1998 industry, government agencies, and nongovernmental organizations established a voluntary conservation program for whale watching in the northeast region of the United States, with the intent to avoid collisions with and harassment of endangered whales by commercial and recreational whale‐watching vessels. One important aspect of the program was the establishment of 3 speed zones within specific distances of whales. We wanted to determine the level of compliance with this aspect of the program to gauge its efficacy and gain insights into the effectiveness of voluntary measures as a conservation tool. Inconspicuous observers accompanied 46 commercial whale‐watching trips from 12 companies in 2003 (n= 35) and 2004 (n= 11). During each trip, vessel position and speed were collected at 5‐second intervals with a GPS receiver. Binoculars with internal laser rangefinders and digital compasses were used to record range and bearing to sighted whales. We mapped whale locations with ArcGIS. We created speed‐zone buffers around sighted whales and overlaid them with vessel‐track and speed data to evaluate compliance. Speeds in excess of those recommended by the program were considered noncompliant. We judged the magnitude of noncompliance by comparing a vessel's maximum speed within a zone to its maximum recorded trip speed. The level of noncompliance was high (mean 0.78; company range 0.74–0.88), some companies were more compliant than others (p= 0.02), noncompliance was significantly higher in zones farther from whales (p < 0.001), and operators approached the maximum speed capabilities of their vessel in all zones. The voluntary conservation program did not achieve the goal of substantially limiting vessel speed near whales. Our results support the need for conservation programs to have quantifiable metrics and frequent evaluation to ensure efficacy.     

Assessment of Management to Mitigate Anthropogenic Effects on Large Whales

United States and Canadian governments have responded to legal requirements to reduce human‐induced whale mortality via vessel strikes and entanglement in fishing gear by implementing a suite of regulatory actions. We analyzed the spatial and temporal patterns of mortality of large whales in the Northwest Atlantic (23.5°N to 48.0°N), 1970 through 2009, in the context of management changes. We used a multinomial logistic model fitted by maximum likelihood to detect trends in cause‐specific mortalities with time. We compared the number of human‐caused mortalities with U.S. federally established levels of potential biological removal (i.e., species‐specific sustainable human‐caused mortality). From 1970 through 2009, 1762 mortalities (all known) and serious injuries (likely fatal) involved 8 species of large whales. We determined cause of death for 43% of all mortalities; of those, 67% (502) resulted from human interactions. Entanglement in fishing gear was the primary cause of death across all species (n = 323), followed by natural causes (n = 248) and vessel strikes (n = 171). Established sustainable levels of mortality were consistently exceeded in 2 species by up to 650%. Probabilities of entanglement and vessel‐strike mortality increased significantly from 1990 through 2009. There was no significant change in the local intensity of all or vessel‐strike mortalities before and after 2003, the year after which numerous mitigation efforts were enacted. So far, regulatory efforts have not reduced the lethal effects of human activities to large whales on a population‐range basis, although we do not exclude the possibility of success of targeted measures for specific local habitats that were not within the resolution of our analyses. It is unclear how shortfalls in management design or compliance relate to our findings. Analyses such as the one we conducted are crucial in critically evaluating wildlife‐management decisions. The results of these analyses can provide managers with direction for modifying regulated measures and can be applied globally to mortality‐driven conservation issues. Evaluación del Manejo para Mitigar Efectos Antropogénicos sobre Ballenas Mayores     

Feeding of western gray whales during a seismic survey near Sakhalin Island, Russia

Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental) on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island. M.W. Newcomer, deceased     

Distribution and abundance of western gray whales during a seismic survey near Sakhalin Island, Russia

Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary known feeding area of the endangered western gray whale (Eschrichtius robustus) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution, abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective, the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess (a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related variable (seg3d, i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total) has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding area remained stable during the seismic survey. M. W. Newcomer, Deceased.     

Behavioral games involving a clever prey avoiding a clever predator: An individual-based model of dusky dolphins and killer whales

Faced with an intermittent but potent threat, animals exhibit behavior that allows them to balance foraging needs and avoid predators and over time, these behaviors can become hard-wired adaptations with both species trying to maximize their own fitness. In systems where both predator and prey share similar sensory modalities and cognitive abilities, such as with marine mammals, the dynamic nature of predator-prey interactions is poorly understood. The costs and benefits of these anti-predator adaptations need to be evaluated and quantified based on the dynamic engagement of predator and prey. Many theoretic models have addressed the complexity of predator-prey relationships, but few have translated into testable mechanistic models. In this study, we developed a spatially-explicit, geo-referenced, individual-based model of a prototypical adult dusky dolphin off Kaikoura, New Zealand facing a more powerful, yet infrequent predator, the killer whale. We were interested in two primary objectives, (1) to capture the varying behavioral game between a clever prey and clever predator based on our current understanding of the Kaikoura system, (2) to compare evolutionary costs vs. benefits (foraging time and number of predator encounters) for an adult non-maternal dusky dolphin at various levels of killer whale-avoidance behaviors and no avoidance rules. We conducted Monte Carlo simulations to address model performance and parametric uncertainty. Mantel tests revealed an 88% correlation (426 × 426 distance matrix, km²) between observed field sightings of dusky dolphins with model generated sightings for non-maternal adult dusky dolphin groups. Simulation results indicated that dusky dolphins incur a 2.7% loss in feeding time by evolving the anti-predator behavior of moving to and from the feeding grounds. Further, each evolutionary strategy we explored resulted in dolphins incurring an additional loss of foraging time. At low killer whale densities (appearing less than once every 3 days), each evolutionary strategy simulated converged towards the evolutionary cost of foraging, that is, the loss in foraging time approached the 2.7% loss experienced by evolving near shore-offshore movement behavior. However, the highest level of killer whale presence resulted in 38% decreases in foraging time. The biological significance of these losses potentially incurred by a dusky dolphin is dependent on various factors from dolphin group foraging behavior and individual energy needs to dolphin prey availability and behavior.     

Effects of Nonylphenol on immune function of female Sprague-Dawley rats

Nonylphenol (NP) is the final biodegradation product of nonylphenol polyethoxylates, which are widely used as surfactants in domestic and industrial products. NP was reported to exert estrogenic actions and shown to potentially adversely affect reproductive functions. However, NP influence on immune system function remains unclear. To address this issue, the effects of NP on spleen and thymus were examined in this study. Female Sprague-Dawley rats were treated with NP orally at doses of 0, 20, 80, or 200 mg/kg respectively. Data showed that NP increased the levels of natural killer (NK) cells and natural killer T (NKT) cells in peripheral blood and decreased the levels of interleukin-4 (IL-4) and interferon gamma (IFN-γ) in serum. These findings suggest that exposure to NP by oral route may induce adverse effects on the spleen and thymus and affect the immune function of female rats.     

Exploring the effects of reductions in krill biomass in the Southern Ocean on blue whales using a state-dependent foraging model

Many species of baleen whales were hunted to near extinction in the Southern Hemisphere. The recovery of these populations will be affected by the availability of krill, a major dietary component, in the Southern Ocean. We combine a novel energetics model for baleen whales with a state dependent foraging model to explore the impacts of an expanding krill fishery on baleen whales. We parameterize the model for blue whales, but with simple modifications it could be applied to most baleen whales. We predict that an expanding fishery will have a small but significant impact on the blue whale population through decreased birth rates. However, spreading the catch limit throughout the range of krill can reduce these effects. In addition, whales may be able to reduce these impacts through adaptive changes in foraging behavior. The relationship between krill abundance and blue whale foraging and reproductive success is nonlinear, such that larger reductions in krill biomass, potentially following a loss of sea ice due to climate change, could have a much larger negative impact on the recovery of blue whales.     

气动马达降噪研究

针对石油钻井工艺使用气动马达产生的噪声影响,对其污染特性进行了探讨,研究选定了气动马达消声器,经现场使用井场周围噪声值可以降低8～16dB（A）,达到了既不影响气动马达的排气功率,又有利于改善井场周围声学环境的效果。     

水中除草剂阿特拉津的测定

采用二氯甲烷液液萃取-氮吹浓缩-丙酮定容去除干扰物,用气相色谱检测水中的阿特拉津,根据保留时间定性,外标法定量.本方法适用于水中阿特拉津的残留量分析,最低检测浓度为4.51×10-2 μg∕L.