Preventing declines in common species is key to sustaining the structure and function of marine ecosystems. Yet for many common marine mammals, including oceanic dolphins, statistical power to detect ...declines remains low due to patchy distribution and large variability in group sizes. In this study, population viability analyses (PVA) were used to model the dynamics of four oceanic dolphin populations off the United States West Coast: eastern North Pacific long-beaked common dolphins (
Delphinus delphis capensis
), short-beaked common dolphins (
D. delphis delphis
), Pacific white-sided dolphins (
Lagenorhynchus obliquidens
), and “offshore” common bottlenose dolphins (
Tursiops truncatus
). We calibrated the PVA with life-history tables, studies on proxy species, and stock assessment reports. We explored the sensitivity of populations to demographic variation and projected how they may respond to changes in three sublethal threats (prey limitation, ocean noise, and chemical pollution) and one lethal threat (fisheries bycatch). We found the most serious projected declines in long-beaked common dolphins, which showed the lowest birth rate. Most threat scenarios resulted in declines that would not be detected by existing monitoring programs in the United States, which are among the most data-rich surveys of their kind. The cumulative effects of the three sublethal stressors exceeded the effect of the one lethal stressor (fisheries bycatch). To implement pro-active management and monitoring programs, anticipating which cetaceans are more at risk and which anthropogenic threats could cause declines is paramount. Our study highlights the value of model testing with PVA when monitoring data are poor, thereby identifying priorities for future research, monitoring, and management.
Autologous stem cell transplantation (ASCT) remains a mainstay in the treatment of multiple myeloma (MM). While the procedure is generally safe, toxicities associated with high-dose melphalan ...conditioning are common and significantly affect patient quality of life. Recently, a propylene glycol-free melphalan formulation (PG-free MEL; Evomela®) was approved by the United States Food and Drug Administration as an ASCT-conditioning regimen for MM. PG-free MEL is more soluble and stable than propylene glycol-solubilized melphalan (PG-solubilized MEL; Alkeran®). As such, there is speculation that it could decrease toxicities and increase the efficacy of ASCT. We compared the outcomes of patients conditioned with PG-free MEL (n = 216) to PG-solubilized MEL (n = 200) at our institution. The baseline characteristics were similar between the two groups. After Day +0, there were no differences in terms of hospitalizations, neutropenic fevers, intravenous granisetron requirement, World Health Organization grade ≥ 2 oral/esophageal mucositis, intravenous fluid requirement, or narcotic requirement. However, PG-free MEL patients had a higher incidence of diarrhea, which was mostly C. difficile-negative (82% vs. 71%, P = 0.015*). Day + 100 hematologic responses and progression-free survival after ASCT were comparable. In summary, we demonstrate that switching to PG-free MEL did not significantly reduce short-term complications of ASCT or improve outcomes in MM.
Zoo and aquarium breeding programs rely on accurate pedigrees to manage the genetics and demographics of captive populations. Breeding recommendations are often encumbered, however, by unknown ...parentage. If an individual has any amount of unknown ancestry, the relationships between that individual and all other individuals in a population are ambiguous, and breeding recommendations cannot be tailored to maximize genetic diversity and minimize inbreeding. In those situations, breeding program management might be improved by the incorporation of molecular data. We developed microsatellite markers for the parma wallaby (Macropus parma) and investigated how genetic data might be used to improve the management of the captive population. The parma wallaby is a small marsupial found in fragmented forests near the coast of New South Wales, Australia. Because the species is of conservation concern, the captive population in North America is managed by recurring breeding recommendations. The effectiveness of the population's management is hampered, however, because over half of the individuals have some amount of unknown ancestry. We used microsatellite data to resolve unknown parentage, described how molecular estimates of relatedness might inform future breeding recommendations, and used computer simulations to investigate how molecular estimates of relatedness among founders might contribute to the genetic management of the population. Our results indicated that microsatellite appraisals of parentage were useful with respect to clarifying pedigrees but that molecular assessments of founder relatedness provided very marginal benefits with regard to the preservation of genetic diversity and the avoidance of inbreeding.
Although population viability analysis (PVA) can be an important tool for strengthening endangered species recovery efforts, the extent to which such analyses remain embedded in the social process of ...recovery planning is often unrecognized. We analyzed two recovery plans for the Mexican wolf that were developed using similar data and methods but arrived at contrasting conclusions as to appropriate recovery goals or criteria. We found that approximately half of the contrast arose from uncertainty regarding biological data, with the remainder divided between policy-related decisions and mixed biological-policy factors. Contrasts arose from both differences in input parameter values and how parameter uncertainty informed the level of precaution embodied in resulting criteria. Policy-related uncertainty originated from contrasts in thresholds for acceptable risk and disagreement as to how to define endangered species recovery. Rather than turning to PVA to produce politically acceptable definitions of recovery that appear science-based, agencies should clarify the nexus between science and policy elements in their decision processes. The limitations we identify in endangered-species policy and how PVAs are conducted as part of recovery planning must be addressed if PVAs are to fulfill their potential to increase the odds of successful conservation outcomes.
In recognition of the fact that orang-utans (Pongo spp.) are severely threatened, a meeting of orang-utan experts and conservationists, representatives of national and regional governmental and ...non-governmental organizations, and other stakeholders, was convened in Jakarta, Indonesia, in January 2004. Prior to this meeting we surveyed all large areas for which orang-utan population status was unknown. Compilation of all survey data produced a comprehensive picture of orang-utan distribution on both Borneo and Sumatra. These results indicate that in 2004 there were c. 6,500 P. abelii remaining on Sumatra and at least 54,000 P. pygmaeus on Borneo. Extrapolating to 2008 on the basis of forest loss on both islands suggests the estimate for Borneo could be 10% too high but that for Sumatra is probably still relatively accurate because forest loss in orang-utan habitat has been low during the conflict in Aceh, where most P. abelii occur. When those population sizes are compared to known historical sizes it is clear that the Sumatran orang-utan is in rapid decline, and unless extraordinary efforts are made soon, it could become the first great ape species to go extinct. In contrast, our results indicate there are more and larger populations of Bornean orang-utans than previously known. Although these revised estimates for Borneo are encouraging, forest loss and associated loss of orang-utans are occurring at an alarming rate, and suggest that recent reductions of Bornean orang-utan populations have been far more severe than previously supposed. Nevertheless, although orang-utans on both islands are under threat, we highlight some reasons for cautious optimism for their long-term conservation.
Small cetaceans face persistent threats from fisheries interactions, making effective mitigation a priority for conservation. In southwest Florida, interactions come primarily from small-scale ...recreational hook and line and trap/pot fisheries, with regional stranding network partners working with federal agency managers to assess and intervene as possible in cases of live animal entanglement. Evaluating success of intervention cases is difficult due to financial and logistical constraints which may preclude detailed follow-up monitoring. Survival over the initial 6 weeks post-release has been used as a marker of short-term success for small-cetacean rescue and/or rehabilitation cases. Early intervention prior to stranding, especially via remote disentanglement or rescue and immediate re-release onsite, can save entangled free-ranging dolphins facing life-threatening anthropogenic injuries. However, given the costs associated with interventions, it is important to understand the benefits of these endeavors not only to save individuals, but also to establish if and how saved individuals contribute to social functioning, survival and reproduction within small, resident populations facing multiple concurrent threats. Here we provide evidence from 27 well-documented common bottlenose dolphin (
Tursiops truncatus
) intervention cases during 1985–2019 where follow-up monitoring over multiple years sheds light on the longer-term success of these efforts and potential benefits to local populations. Nearly all rescued individuals (92%) survived longer than 6 weeks post-release (mean minimum survival period = 5 years, range 0–35 years), with 13 still observed frequently within their prior resident communities, in good physical health, and engaging in normal behavior. Survivorship rates did not decline substantially between 1 and 5 years post-rescue, meaning survival beyond 1 year may be a useful benchmark of long-term success. Rescued females that reached reproductive maturity (
n
= 4) have produced 12 post-intervention offspring to date. Social network analysis and demographic modeling applied to cases from the long-term resident community in Sarasota Bay confirmed that animals maintain social connections post-intervention and that interventions result in higher population growth rates. While not every intervention succeeds, this study demonstrates the conservation value of pre-stranding interventions which allow individuals that otherwise would be lost to remain viable and productive members of local populations when prevention of anthropogenic injury is not possible.
We conducted a retrospective study comparing posttransplant outcomes between myeloma patients receiving conditioning melphalan on day-2 vs day-1 for autologous stem cell transplant. Between January ...2017 and December 2018, 201 patients received melphalan on day-2 and 166 on day-1 prior to stem cell infusion. Baseline disease and clinical characteristics between the two groups were similar. Although rates of hospitalization were similar between the cohorts, duration of hospital admission was longer for day-1 (median 7 days for day-1 vs 5 days for day-2, p = 0.003). Rates of fever were higher in the day-1 cohort (69% vs 49%, p = 0.0002). Time to platelet and neutrophil engraftment was significantly longer in the day-1 cohort (platelet engraftment median days 17 for day-1 vs 15 for day-2, p < 0.0001, neutrophil engraftment median days 16 for day-1 vs 16 for day-2, p = 0.025). Overall response rate was similar between the cohorts (99% for day-1, vs 100% for day-2). Day-2 melphalan infusions should be considered in preference for day-1 protocols, given the clinically significant delay in platelet and neutrophil engraftment and longer duration of hospitalization with day-1 infusions.
Many breeding programs managed by zoos and aquariums employ strategies that minimize mean kinship as a way of retaining genetic diversity (MK strategies). MK strategies depend on accurate and ...complete pedigrees, but population founders are generally assumed to be unrelated and not inbred. This assumption was historically necessitated by the unavailability of data on founder relationships, but with DNA techniques it is sometimes now possible to estimate those relationships. We used computer simulations to investigate the impact of founder assumptions on the effectiveness of MK strategies. Individuals with known pedigrees were managed in groups of 10, 30, and 100 founders at two different rates of reproduction and two different degrees of founder relationship. The impact of assuming founders were unrelated was quantified by calculating the differences in gene diversity and inbreeding that were observed between simulations that used known relationships and simulations that assumed founders were unrelated. Results indicated that utilizing known relationships retained 0-2% more gene diversity over ten generations than assuming founders were unrelated, with specific results dependent on the conditions of a given scenario. Similar results were observed for inbreeding, with long-term levels of inbreeding being 0-2% lower when relationships were known. There were higher benefits to knowing founder relationships as reproductive rate increased, as well as when full-siblings were included in small groups of founders. Overall, however, long-term benefits gained from knowing founder relationships were generally small. Therefore, MK strategies probably often produce near optimal results when standard founder assumptions are made.
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