Oak Conservation Research Articles

IDENTIFICATION AND RETROSPECTIVE EVALUATION OF A FILARIOID NEMATODE SPECIES IN MANAGED GRASSHOPPER SPARROWS (AMMODRAMUS SAVANNARUM).

The grasshopper sparrow (Ammodramus savannarum) is a species of ground-dwelling passerine bird with 12 different subspecies. The Florida subspecies (Ammodramus savannarum floridanus) is classified as federally endangered, with the most common threats including habitat loss, nest predation, and floods. A managed breeding program was established at White Oak Conservation (Yulee, FL) in 2015 with eastern grasshopper sparrows (Ammodramus savannarum pratensis) as a model for breeding Florida grasshopper sparrows as part of an assurance colony. A filarioid parasite species (Aproctella sp.) was characterized by PCR after identification by blood films and postmortem examinations of both subspecies housed at White Oak Conservation. This Aproctella species was distinct from others with available sequence. Records from 157 eastern and Florida grasshopper sparrows were reviewed, and correlations between presence of filariasis and subspecies, sex, body condition score, and presence of systemic isosporosis, squamous metaplasia, coelomitis, airsacculitis, or a combination of conditions were investigated. Twenty-nine (18.5%) birds (13 of 71 Florida grasshopper sparrows; 16 of 86 eastern grasshopper sparrows) were positive for filariasis by blood film review, grossly or by tissue imprint at postmortem examination, or histologically. Filariasis was significantly correlated with systemic isosporosis, coelomitis, and airsacculitis; was not correlated with subspecies, sex, or squamous metaplasia; and had a questionable correlation with body condition score. This report provides evidence that this Aproctella species has potential to contribute to morbidity and mortality in the grasshopper sparrow. This information will be helpful for implementing effective measures against suspected vectors and for the development of best practice strategies for the health management of the species in breeding programs.

DETECTION AND DIFFERENTIATION OF TRICHURIS IN GIRAFFE (GIRAFFA CAMELOPARDALIS) UNDER HUMAN CARE.

Trichuris spp. are nematode parasites infecting many species, including domestic and wild ruminants in zoological and wildlife parks worldwide. These nematodes cause significant morbidity in giraffes (Giraffa camelopardalis) and other hoofstock. Parasite transmission between ruminant species is well reported; however, relative to domestic species, little is known about Trichuris infections in giraffes under human care. We hypothesized that Trichuris spp. differ between individual giraffes in different US regions, suggesting giraffes are susceptible to Trichuris from other ruminant hosts. The study sites used to assess this hypothesis included The Wilds in Cumberland, Ohio; Fossil Rim Wildlife Center in Glen Rose, Texas; White Oak Conservation in Yulee, Florida; and Binder Park Zoo in Battle Creek, Michigan. Trichuris eggs were collected from the feces of 14 individual giraffes located at the four different study sites and from soil samples from the enclosures where Trichuris-positive giraffes were housed. The eggs were isolated and their genes were amplified by PCR and compared at the molecular level. Trichuris samples from four giraffe hosts and one soil site were sequenced and portions of the cox1 and 18S genes compared. This study found that >12 eggs per gram of fecal-derived Trichuris eggs must be present to amplify Trichuris-specific DNA. The Trichuris spp. found in the majority of giraffes in this study were most similar to T. ovis and T. discolor, and one giraffe sample had greater similarity to T. skrjabini and T. leporis.

Identification of an Emaravirus in a Common Oak (Quercus robur L.) Conservation Seed Orchard in Germany: Implications for Oak Health

We observed the health status of oak trees in a conservation seed orchard for over twenty years, focusing on characteristic virus-suspected symptoms. The orchard was established in 1992 in Kreuztal, North Rhine-Westphalia (Germany) with 1302 seedlings in 186 clusters. The number of seedlings showing chlorotic ringspots and mottle on leaves has fluctuated annually, but has increased from 3.3% to 12.1% in the last 20 years; the number of affected clusters has risen from 8% to 25.9%. A scientific breakthrough was the identification of a novel virus related to members of the genus Emaravirus in diseased oak by high-throughput sequencing (HTS). Screening of the oak seedlings in three consecutive years, using a newly established virus-specific diagnostic reverse transcription polymerase chain reaction (RT-PCR), confirmed the virus infection and revealed a close to 100% association between the observed leaf symptoms and the novel virus. As no other plant virus could be identified in the HTS-datasets, we assume the novel virus is primarily causing the symptoms. To reliably detect the novel virus in oaks, RT-PCR targeting the viral RNA3 or RNA4 should be applied in routine testing of symptomatic leaf tissue. It was obvious that most groups with virus-infected plants cluster, with only five out of the 42 affected groups being offside, not bordering on other affected groups of plants. There was no clear correlation between the detection of the virus and the overall vitality of the seedlings. There was no relation between seedling performance and presence or absence of viral infection. Forecasts on the future growth behavior of these virus-infected oak trees are therefore not possible.

Applying science to pressing conservation needs for penguins.

More than half of the world's 18 penguin species are declining. We, the Steering Committee of the International Union for Conservation of Nature Species Survival Commission Penguin Specialist Group, determined that the penguin species in most critical need of conservation action are African penguin (Spheniscus demersus), Galápagos penguin (Spheniscus mendiculus), and Yellow‐eyed penguin (Megadyptes antipodes). Due to small or rapidly declining populations, these species require immediate scientific collaboration and policy intervention. We also used a pairwise‐ranking approach to prioritize research and conservation needs for all penguins. Among the 12 cross‐taxa research areas we identified, we ranked quantifying population trends, estimating demographic rates, forecasting environmental patterns of change, and improving the knowledge of fisheries interactions as the highest priorities. The highest ranked conservation needs were to enhance marine spatial planning, improve stakeholder engagement, and develop disaster‐management and species‐specific action plans. We concurred that, to improve the translation of science into effective conservation for penguins, the scientific community and funding bodies must recognize the importance of and support long‐term research; research on and conservation of penguins must expand its focus to include the nonbreeding season and juvenile stage; marine reserves must be designed at ecologically appropriate spatial and temporal scales; and communication between scientists and decision makers must be improved with the help of individual scientists and interdisciplinary working groups.

Influence of a climatic gradient on genetic exchange between two oak species.

In plant groups with limited intrinsic barriers to gene flow, it is thought that environmental conditions can modulate interspecific genetic exchange. Oaks are known for limited barriers to gene flow among closely related species. Here, we use Quercus as a living laboratory in which to pursue a fundamental question in plant evolution: Do environmental gradients restrict or promote genetic exchange between species? We focused on two North American oaks, the rare Quercus dumosa and the widespread Q. berberidifolia. We sampled intensively along a contact zone in California, USA. We sequenced restriction site-associated DNA markers and measured vegetative phenotype. We tested for genetic exchange, the association with climate, and the effect on phenotype. There is evidence for genetic exchange between the species. Admixed plants are found in areas of intermediate climate, while less admixed plants are found at the extremes of the climatic gradient. Genetic and phenotypic patterns are out of phase in the contact zone; some plants display the phenotype of one species but are genetically associated with another. Our results support the hypothesis that a strong climatic gradient can promote genetic exchange between species. The overall weak correlation between genotype and phenotype in the contact zone between the species suggests that genetic exchange can lead to the breakdown of trait combinations used to define species. This incongruency predicts ongoing problems for conservation of Q. dumosa, with implications for conservation of other oaks.

Parathyroid, Thyroid and Recurrent Laryngeal Nerve Anatomy in an Indian Rhinoceros (Rhinoceros unicornis)

IntroductionThe parathyroid gland was first identified in the Indian rhinoceros in 1849 by Sir Richard Owen. We performed a necropsy in an Indian rhinoceros, recapitulating Owen’s dissection and display what appear to be the initial identification of the recurrent laryngeal nerve in situ and the anatomy and histology of the largest rhinoceros parathyroid glands yet identified.Materials and methodsPatrick T. Rhino, a 41-year-old Indian rhinoceros was born in 1974. His early years were unremarkable. In 2006, he was donated to White Oak Conservation in Yulee, Florida, where he bred and sustained minor injuries. In his geriatric years, he developed a cataract and degenerative joint disease (DJD). At age 41, he developed progressive ataxia and lameness and was euthanized to minimize suffering when he was unable to stand. ROS, FH, SH and medication history were unremarkable. Physical exam was age and species appropriate. Pre-mortem serum demonstrated: creat 1.8 mg/dL (0.8–2.1), calcium 10.6 mg/dL (9.7–13.1), phos 3.8 mg/dL (2.5–6.7), alk phos 69 U/L (26–158) and intact PTH 44.1 pg/mL (rhinoceros reference range: unknown). Necropsy revealed intervertebral DJD with thoracic spondylosis, which combined with osteoporosis, resulted in thoracic myelopathy and ataxia. The neck block was sent in formalin to the Yale University School of Medicine.ResultsDetailed dissection was performed under loupe magnification. Presumed structures were photographed in situ and biopsied. The thyroid was identified deep to the strap muscles, received its blood supply from the inferior and superior thyroid arteries and was blue in color. The right recurrent laryngeal nerve, identified and photographed in situ for the first time in the rhinoceros, was deep to the inferior thyroid artery and was traced throughout its cervical course. Single parathyroid glands identified on the lateral thyroid lobes received their blood supply from the inferior thyroid arteries and were confirmed histologically. They appear to be the largest parathyroids yet identified in the rhinoceros with estimated weights of 6,280 and 11,000 mg, respectively. Although the etiology of the parathyroid gland enlargement is unknown, the specimen has been preserved recapitulating the dissection performed by Sir Richard Owen.ConclusionThe parathyroids, thyroid and recurrent laryngeal nerve were identified in an Indian rhinoceros. This appears to be the first display of the rhinoceros recurrent laryngeal nerve in situ, and the parathyroid glands are the largest yet identified in the rhinoceros.

Tissue Culture Using Mature Material for the Conservation of Oaks

Tissue culture using mature-phase plant material is a useful tool for species conservation, but can be a challenge with oak (Quercus) species, often resulting in low growth and survival. Two different tissue culture media were compared and used to determine whether there was a survival, growth, or contamination response pattern in species representing three North American oak taxonomic sections: red oaks (section Lobatae), white oaks (section Quercus), and golden oaks (section Protobalanus). Mature phase cuttings were harvested in springtime from 12 oak species: arkansas oak (Q. arkansana), canby oak (Q. canbyi), slender oak (Q. graciliformis), nuttall oak (Q. texana), boynton sand post oak (Q. boyntonii), california scrub oak (Q. dumosa), engelmann oak (Q. engelmannii), gambel oak (Q. gambelii), canyon live oak (Q. chrysolepis), palmer oak (Q. palmeri), island oak (Q. tomentella), and huckleberry oak (Q. vacciniifolia). Excised shoot-tip explants were placed onto either Lloyd and McCown woody plant (WP) medium or Gresshoff and Doy (GD) medium. More growth responses and longer survival times were seen on explants grown on the WP medium than GD medium. Explants originating from species native to xeric habitats or those with smooth, glabrous young leaves had significantly higher contamination rates. Although no significant differences were found when grouped by taxonomic section, survival, growth, and contamination varied significantly by species. These findings contribute to the process of establishing tissue culture methods using mature oak material, particularly in relation to medium selection and sterilization protocols, which is critical to the conservation of this iconic group of species.

Social and Ecological Consequences of Commercial Harvesting of Oak for Firewood in Bhutan

Oak (Quercus spp.) is an important commercially harvested firewood resource in Bhutan. An oak firewood shortage began in 2000–2009, when demand, spurred by urban domestic and institutional use, began to exceed supply, resulting in overcutting of oak-dominant forest, which affected tree species diversity. This study solicited urban and rural perceptions on oak firewood availability, alternative firewood sources, and whether harvest is consistent with oak conservation, and conducted an assessment of the consequences of commercial oak firewood harvest for species diversity and regeneration. Semistructured interviews and focus group discussions were conducted, and regeneration was sampled on unharvested and commercially harvested oak firewood stands. Urban and rural respondents reported that the oak firewood supply was diminishing. Rural respondents said that oak firewood, leaf litter, fodder, and wood for handles for agricultural implements were abundantly available in the past but that, with the increase in population, these products have become less available, a trend that is likely to continue in the future. Urban respondents overwhelmingly chose electricity as an oak firewood substitute because it was associated with clean energy, improved sanitation, and forest conservation. Electricity should be promoted as an oak firewood substitute in urban homes. Oak as a source of firewood, leaf litter, fodder, and handles for agricultural implements is indispensable for sustaining rural livelihoods, and harvest consistent with conservation needs to be practiced. Tree species diversity and regeneration were not significantly higher in unharvested stands compared to harvested stands, indicating that oak firewood harvest may not have impacted species diversity. The findings support banning commercial harvesting of green oak trees for firewood and promoting electricity as an alternative energy source as the most important oak conservation measures.

Land use and management effects on carbon and nitrogen in Mediterranean Cambisols

In Mediterranean Europe, dehesa is the most widespread agroforestry system, that integrates forestry with agricultural and livestock management practices. It is characterized by the conservation of forest oaks to provide environmental services including carbon capture and storage. During the past two decades, many dehesa areas have been converted to olive groves with little information regarding long-term effects on soil organic carbon (SOC) distribution, total nitrogen (TN) concentrations, C:N relation, or stratification ratios (SR) throughout the soil profile. Understanding carbon and nitrogen dynamics is essential for making appropriate land management decisions. Our objective was to qualify SOC, TN, and profile SRs after Eutric Cambisols were converted from dehesa to olive groves using organic or conventional management practices for approximately 20 years. We analyzed soil profile samples from 45 farms in 2009 in Southern Spain. Olive groves managed using organic practices had more SOC stock (73.58Mgha−1) and TN stock (7.10Mgha−1) than dehesa. SOC and TN decreased with depth under both land uses and managements. Overall, organic farming (OF) resulted in higher SOC and TN levels than conventional tillage (CT), but the SRs were similar for both land uses and management strategies. These results suggest that, in general, these soils do not have degradation problems. Only in SR2 (defined by Ap-A/C) of SOC and SR2 of TN, showed significant differences and soils under OF had higher quality than under CT. By contrast, the C:N stratification ratio was similar in all land uses and management.

Stratification ratio of soil organic C, N and C:N in Mediterranean evergreen oak woodland with conventional and organic tillage

The Mediterranean evergreen oak woodland (MEOW-dehesa) is the most widespread agroforestry system in Mediterranean Europe and integrates forestry, agricultural and livestock practices. The MEOW-dehesa is a grazing system with evergreen Quercus ilex spp. ballota. It is characterized by the conservation of forest oaks (Quercus spp.) and provides environmental benefits such as carbon capture and storage in soils.The effect of conventional tillage (CT) and organic tillage (OT) on the distribution of soil organic carbon (SOC), total nitrogen (TN) and C:N ratios has not been well documented in the MEOW-dehesa. The objective of this paper is to study these parameters in the MEOW-dehesa in two soil types (Leptosols and Cambisols) and two management systems, OT for 20 years and CT. The stratification ratio (SR) of SOC, TN and C:N ratio is also evaluated. An analysis is performed on 85 soil profiles over the 2005–2009 period in southern Spain.The SR of SOC in Cambisols was greater under OT than CT, ranging from 1.25 to 1.42 and from 1.3 to 1.6 under CT and OT, respectively. The SR of TN for 0–20.9cm, 20.9–55.5cm and 55.5–102.1cm depth was greater under OT than under CT. The OT also increased the stratification of the C:N ratio compared to CT.

Development and Characterization of Genomic and Gene-Based Microsatellite Markers in North American Red Oak Species

Oaks (Quercus: Fagaceae) are ecological and economic keystones of many forested ecosystems but effective genetic management strategies are hindered by high levels of phenotypic plasticity within species and frequent hybridization among them. These same features, however, make oak communities suited for the study of speciation, hybridization, and genetic adaptation. Efforts to develop new and to adapt existing genomic resources to less-studied members of this genus should not only improve oak conservation and management but also aid the study of fundamental evolutionary processes. Here, we present a suite of 27 highly polymorphic simple sequence repeat (SSR) markers tested in four North American red oak (Quercus section Lobatae) species: Q. rubra, Q. ellipsoidalis, Q. coccinea, and Q. velutina. Five markers are genomic SSRs (gSSRs) — four novel and one previously transferred from Q. petraea — and 22 are gene-based SSRs derived from Q. robur and Q. petraea expressed sequence tags (EST-SSRs). Overall, levels of polymorphism detected with these primer pairs were high, with gene diversity (He) averaging 0.66 across all loci in natural populations. In addition, we show that EST-SSR markers may have the potential to detect divergent selection at stress-resistance candidate genes among closely related oak species.

Oak conservation maintains native grass stands in an oak woodland-annual grassland system

Mediterranean oak woodlands serve as working landscapes and biodiversity hotspots. These landscapes have undergone dramatic land conversion, which continues to threaten their conservation. Shifting focus from traditional management practices to a balance of conservation and production goals is a key challenge on working landscapes, and evaluating potential tradeoffs and synergies among goals will be a critical first step. California’s oak woodlands have undergone marked transformations via removal of Quercus douglasii and other woody plants to enhance forage production. Within the annual grass-dominated matrix, Q. douglasii likely functions as a foundation species—providing potential habitat for native plants, such as Nassella pulchra. Via a cross-sectional survey, we examined spatial occurrence of N. pulchra relative to Q. douglasii trees across three cattle-grazed fields, which had previously undergone vegetation manipulation. We hypothesized that Q. douglasii trees provide spatial niches for N. pulchra, with bunchgrass densities declining with greater distances from Q. douglasii stems. Plots (n = 712) were located along northern/southern transects of 89 trees. N. pulchra densities and site characteristics were surveyed in 2002 and 2005. Generalized linear mixed model regression analysis revealed a significant plot position by community type interaction: N. pulchra densities significantly declined with increasing distance from target trees at grassland sites; this trend was apparent at savanna sites and no trend was observed at woodland sites, which were likely under the influence of neighboring trees. Information on native species relationships can be utilized by managers to balance agricultural production and native species conservation goals across working landscapes.

CONGEN-2010: A Semester in a Fortnight

The AGA-sponsored 2010 workshop on ‘‘Recent Advances in Conservation Genetics’’ was held 7–20 February, 2010, at the impressive White Oak Conservation Center in Yulee, Florida. This was the 9th edition of the workshop, which has expanded beyond its first home at the Smithsonian Conservation Biology Institute in Front Royal, Virginia, to include versions in Florida, Brazil, Hawaii, and the Republic of Panama. The goal of these workshops is to teach the participants how to develop and interpret a variety of genetic data for application to pressing problems in biodiversity conservation. The workshop was organized by Dr Stephen O’Brien and members of his Laboratory of Genomic Diversity at the National Cancer Institute, Frederick, Maryland, and several of the lab’s scientists gave extended faculty lectures and assistance during the 2-week workshop. Students at the workshop represented 12 countries, almost every continent, and diverse experience/background levels. They included graduate students, postdocs, biology professors and veterinarians, as well as other scientists interested in learning more about conservation genetics. The schedule was jam-packed with sessions starting at 8:30 AM every day and continuing through evening lectures and late-night computer sessions. Outside the classroom, practical ‘‘laboratory’’ sessions included tissue sampling, blood work, artificial insemination, sperm and egg evaluation and banking, and a wonderful conservation center tour. A half-day field trip to the Okefenokee swamp with the very knowledgeable owner and guides from Okefenokee Adventures provided a mid-workshop break on the middle Sunday. Upon arrival, each attendee was presented with a new laptop computer (donated by Apple for use during the workshop) preloaded with the software for the course and communication tools—servers, calendars, and chat services. This made for very efficient time use, as it wasn’t necessary to delay teaching while software was configured for multiple platforms and operating systems. Theoretical and practical classroom sessions occupied the morning and afternoon time slots, and evenings were reserved for very educational invited lectures that put the daily lessons into a real-world context (Table 1). Time was also allotted for workshop participants to analyze their own data with faculty help. These tutorials always prove popular, as the ‘‘students’’ get one-on-one help from the experts—not only on ‘‘How’’ to organize and analyze their data but why to do it that way, what other possibilities might be evaluated, and how to interpret the differences. Topics covered were both broad and deep. Techniques and data types ranged from SNPs and microsatellites, through DNA bar coding, sequencing, and genomics. Databases, metadata, and sample management were also presented through the ‘‘conservation lens.’’ Specific content included: data mining, databases, bioinformatics, sequence alignment, trait mapping and strategies, molecular dating methodologies, Bayesian inference, ancient DNA, genetic markers, population genetics, microsatellites, DNA sequence data, DNA bar coding, basic and advanced phylogenetics, comparative genomics, microarray and second/third generation sequencing and pyrosequencing technologies, haplotype inference, detecting and measuring selection, host specificity and disease adaptation, parentage analysis, disease pathology and conservation, genetics of domestication, landscape ecology, and an open session on career, financial, and research planning. What the lectures and lecturers really taught, beyond the subject matter presented, was how to do science ‘‘right.’’ The lecturers told their stories thoroughly, including dead-ends pursued, noninformative data and analyses, and tangents of discovery. The value and power of outreach and education were also an integral part of many presentations. Attendee feedback was universally positive, with consistent comments on the practical utility of what was presented. Though I had attended both the Molecular Evolution Workshop and the Advances in Genomics and Bioinformatics Workshop in the past (at MBL/Woods Hole and a recent molecular evolution refresher at the Smithsonian’s National Museum of Natural History), I was still lacking much experience with SNPs, microsatellites, and other populationlevel genetic data analyses. This course extended the data analyses to the population level as none of the other courses had, providing exposure to the methods of most relevance to biodiversity. I would strongly recommend this workshop to scientists of all levels desiring a high-quality immersive introduction to the elements of conservation genetics. The 2011 ConGen workshop will be held September 3–11 in Pantanel, Brazil.

An overview of the assisted reproduction and genome banking activities of White Oak Conservation Center, Yulee, FL, in the service of species conservation

Assisted reproduction includes simple strategies, such as oral progestin to maintain pregnancy and hormone monitoring to predict oestrus for breeding introductions, as well as complex procedures, such as oestrous synchronization and artificial insemination (AI). The primary focus of research at White Oak Conservation Center, Yulee, FL, has been to work towards techniques allowing movement of frozen semen to manage metapopulations rather than translocate animals. Using the Gerenuk Litocranius walleri walleri as a model for threatened antelope, oestrous synchronization and AI were refined to produce four live offspring (from six attempts) using hand restraint rather than anaesthesia for inseminations. Conversely, similar progress with Okapi Okapia johnstoni has been slower. Okapi sperm are highly susceptible to osmotic changes and the physical pressures of the freezing process, which has limited the ability to develop suitable cryopreservation protocols. Storage of frozen semen from highly threatened animals provides insurance against loss of the individual’s genes to the population and, if used for future insemination, can potentially provide new ‘founders’. Biomaterials from both species, including blood and blood products, are preserved in genome resource banks together with samples from other threatened species, including the Florida panther Felis concolor coryi. It is important to note that assisted reproduction in novel species requires significant commitment and continuity from zoological institutions for optimal results.

Oak Conservation and Restoration on Private Forestlands: Negotiating a Social-Ecological Landscape

In the midwestern United States, oak (Quercus spp.) forests are considered critical habitat for conserving biodiversity and are a declining resource. Ecological conditions, such as deer herbivory and competition from more mesic broad-leaved deciduous species, have been linked to poor oak regeneration. In the Midwest, where up to 90% of forestland is privately owned, a greater understanding of social dimensions of oak regeneration success is especially critical to designing effective restoration strategies. We sought to determine factors that serve as direct and indirect constraints to oak restoration and identify policy mechanisms that could improve the likelihood for restoration success. We conducted in-depth qualitative interviews with 32 natural resource professionals working in the Midwest Driftless Area. We found that most professionals anticipate that oak will remain only a component of the future forest. Furthermore, they identified the general unwillingness of landowners to adopt oak restoration practices as a primary driving force of regional forest change. The professionals pointed to interdependent ecological and social factors, occurring at various scales (e.g., economic cost of management, deer herbivory, and exurban residential development) as influencing landowner oak restoration decisions. Professionals emphasized the importance of government cost-share programs and long-term personal relationships to securing landowner acceptance of oak restoration practices. However, given finite societal resources, ecologically- and socially-targeted approaches were viewed as potential ways to optimize regional success.

Framing Conservation on Private Lands: Conserving Oak in Oregon's Willamette Valley

Conserving threatened habitats on private lands requires policies that advance the interests of landowners and natural resource professionals alike. Through qualitative analysis of individual and focus-group interviews, we compared how family forest owners and natural resource professionals frame conservation of threatened habitat: the oak woodlands and savanna in Oregon. Applying constructionism to the analysis and design of specific policies, we explored policy options to facilitate cooperation and avert conflict between these stakeholders. Informants displayed three primary frames in discussions of oak conservation: the human–nature relationship, the rights and obligations of property ownership, and the role of policy in social change. Their motivations to conserve oak and preferences for conservation policy stemmed from their differing uses of these frames. Conservation easements, habitat mitigation banking, and voluntary grass-roots initiatives were three types of policy that seemed to accommodate the frames of both owners and natural resource professionals.

Cardiac Evaluation of Clinically Healthy Captive Maned Wolves (Chrysocyon brachyurus)

The objective of this project was to determine radiographic vertebral heart sizes and electrocardiographic (ECG) and echocardiographic measurements in healthy anesthetized maned wolves (Chrysocyon brachyurus). The wolves, housed at the White Oak Conservation and Smithsonian National Zoo Conservation and Research Centers, were being anesthetized for annual examinations. Cardiac auscultation, thoracic radiographs, a standard 6-lead ECG, and echocardiography were performed on the wolves while they were under general anesthesia. Thirteen maned wolves were evaluated: five males and eight females. Mean age was 6.4 +/- 4.4 years (range, 2-13 years). Mean weight was 26 +/- 2.95 kg (range, 22-32 kg). Low-grade systolic murmurs were auscultated in three of 13 maned wolves. Evaluation of ECGs revealed a sinus rhythm, with a QRS morphology, and mean electrical axis similar to domestic canines. Radiographic evaluation revealed a mean vertebral heart size of 8.27 +/- 0.48 (range, 7.9-8.6). In addition, the cardiac silhouette was seen to elongate, with an increase in sternal contact in older wolves. Echocardiography showed that mitral valve degenerative changes and insufficiency is likely common in older wolves. Visualization of physiologic regurgitation across the mitral and pulmonary valves was common in wolves of all ages. Left ventricular measurements were similar to those reported for healthy dogs, and several variables correlated well with body weight. Two wolves were found to have one to three heartworms in the right pulmonary artery, and degenerative mitral valve disease was determined in maned wolves older than 6 years of age. All of the wolves in this study were on heartworm preventative and tested negative for heartworm antigen at their annual examinations. The results of this study provide reference information for use in the cardiac evaluation of anesthetized maned wolves.

Greenhouse gas mitigation potential of combining forest management and bioenergy substitution: A case study from Central Highlands of Michoacan, Mexico

Key to climate change abatement strategies is the understanding of the comparative carbon mitigation implications of management of native forests oriented to different end-uses such as conservation, conventional management, or integrated management that includes bioenergy. In Mexico 95% of total logging is conducted in native forests, and 80% of it in pine–oak forests. In this paper we compare the carbon mitigation dynamics of mixed native pine–oak forests in Central Mexico under current management – used as a reference scenario – with two alternative scenarios: (a) oak conservation and (b) oak conservation + bioenergy. To estimate the carbon fluxes for each scenario and each forest type we used the CO2FIX V3.1 model, a user-friendly tool designed to calculate all carbon fluxes in forest stands, forest-derived products and bioenergy technologies based on forest slash and industrial residues. The CO2FIX model applies a cohort-type approach to estimate carbon fluxes in mixed or uneven-aged forests where species groups or age cohorts typically show differences in growth, biomass allocation, intra and inter-cohort competition, and mortality. The product module tracks the carbon in products derived from the forests until the decomposition is complete, whereas the bioenergy module compares total greenhouse gas dynamics of reference and alternative bioenergy technologies, applying IPCC guidelines to estimate the carbon equivalence of the various greenhouse gases. We compare the outcome of the three scenarios in a managed community forest of about 11,000 ha in Michoacan, Central Mexico. The carbon mitigation potential after 20 years varied between 8.2 and 19.3 t C/ha for the oak conservation scenario and between 21.6 and 42.9 t C/ha for the oak conservation–bioenergy scenario. The bioenergy scenario results in a continuous stream of about 1.36 t C/ha of carbon benefits per year, whereas the oak conservation scenario will stop accumulating carbon after 40 years, compared to current forest management and energy generation.

Land manager attitudes toward management, regeneration, and conservation of Spanish holm oak savannas (dehesas)

Biological conservation in Spanish dehesas critically depends on the long-term persistence of a holm oak tree layer. Managers of private estates in Cáceres province, Spain, were surveyed about their conservation attitudes and behavior, especially as regards the widespread regeneration failure of oak stands. The aim was to define land-user perspectives on oak conservation in dehesas as basis for the design of suitable oak regeneration programs. Dehesa estates are managed diversely for a variety of goals, with lamb and beef production predominating. Small operations (‘minifundios’) had significantly higher stocking levels than large operations (‘latifundios’). Results suggest that managers strongly appreciate oaks, both for income- and non-income-related motivations like the preservation of real estate value or family tradition. Concern about threats to oak stands like lacking regeneration, oak decline, or conversion in urban areas varied in intensity, but most managers expected major changes for the future. Statistical relationships were established between oak appreciation and socio-economic variables like age, land ownership, years the operation had been owned by the family, and use of oak products. The survey revealed great confusion about existing oak conservation regulations. For long-term support to be assured, policy should orient its efforts toward conservation incentive schemes, environmental education, and technical assistance.

Genetic resource conservation of mediterranean oaks in Spain

Ecological and economical interest of mediterranean species of genus Quercus (Quercus ilex, Q. suber, Q. coccifera) justify the studies and actions focused on conservation of their genetic resources. As an essential basis for the development of conservation strategies, a review of the state of knowledge on these species diversity is offered, mainly referred to genetic variation. Factors determining genetic structure are commented, as well as the relevance of some marginal populations for conservation purposes. In spite of the peculiarities of each species, similar distribution and management lead to common conservation problems. Main threats come from the exploitation models: lack of regeneration, low maturity in coppices, uncontrolled seed movements, etc. Marginal populations have higher risk of disappearance due to their singular characteristics (low demographic size, limitant habitats). These menaces require the adoption of strategies in which the management promote natural regeneration and the evolution of the stands, while at the same time particular risks of each population are considered.