Acute complications in open/miss primary and revision thoracolumbar spine surgery: a descriptive study of the most common complications and treatment of choice.

PURPOSE: Main question The aim of this study is to describe and analyze the frequency of acute perioperative (intraoperatively and 30 days after) complications of open/MISS thoracolumbar spine surgery. Secondary questions A) Describe the treatment of choice for every kind of complication mentioned. B) Perform a bibliographic search and compare the complications described and their frequency with those studied in the manuscript. METHODS: A retrospective cohort of 816 patients undergoing spinal surgery over a two year period was analyzed. Acute complications of 59 patients are described whether those with a greater number of levels required longer periods of hospitalization. RESULTS: The frequency of acute complications was 7.2%. The most common was infection (2.7%), followed by dural tear (1.7%), and screw malpositioning (1%), which is consistent with the current literature. No statistically significant results were observed when comparing the mean length of hospital stay among patients operated on a greater number of levels compared to the rest (P: 0.344; 95% CI: -3.88-10.93). CONCLUSIONS: The subsidiary patient of spinal surgery is getting older and has more comorbidities, and therefore, has a higher risk of complications. Although there are models predicting the risk of complications, they are not used in routine clinical practice. It would be necessary to unify the main criteria and establish guidelines for risk detection and therapeutic algorithms based on new high-quality studies.

Large variance in inbreeding within the Iberian wolf population.

The gray wolf (Canis lupus) population on the Iberian Peninsula was the largest in western and central Europe during most of the 20th century, with its size apparently never under a few hundred individuals. After partial legal protection in the 1970s in Spain, the northwest Iberian population increased to about 300-350 packs and then stabilized. In contrast to many current European wolf populations, which have been connected through gene flow, the Iberian wolf population has been isolated for decades. Here we measured changes on genomic diversity and inbreeding through the last decades in a geographic context. We find that the level of genomic diversity in Iberian wolves is low compared to other Eurasian wolf populations. Despite population expansion in the last 50 years, some modern wolves had very high inbreeding, especially in the recently recolonized and historical edge areas. These individuals contrast with others with low inbreeding within the same population. The high variance in inbreeding despite population expansion seems associated with small-scale fragmentation of the range that is revealed by the genetic similarity between modern and historical samples from close localities despite being separated by decades, remaining differentiated from other individuals that are just over 100 km away, a small distance for a species with great dispersal capacity inhabiting a continuous range. This illustrates that, despite its demographically stable condition, the population would probably benefit from favoring connectivity within the population as well as genetic exchange with other European wolf populations to avoid excessive fragmentation and local inbreeding depression.

Extracellular Tuning of Mitochondrial Respiration Leads to Aortic Aneurysm.

BACKGROUND: Marfan syndrome (MFS) is an autosomal dominant disorder of the connective tissue caused by mutations in the FBN1 (fibrillin-1) gene encoding a large glycoprotein in the extracellular matrix called fibrillin-1. The major complication of this connective disorder is the risk to develop thoracic aortic aneurysm. To date, no effective pharmacologic therapies have been identified for the management of thoracic aortic disease and the only options capable of preventing aneurysm rupture are endovascular repair or open surgery. Here, we have studied the role of mitochondrial dysfunction in the progression of thoracic aortic aneurysm and mitochondrial boosting strategies as a potential treatment to managing aortic aneurysms. METHODS: Combining transcriptomics and metabolic analysis of aortas from an MFS mouse model (Fbn1c1039g/+) and MFS patients, we have identified mitochondrial dysfunction alongside with mtDNA depletion as a new hallmark of aortic aneurysm disease in MFS. To demonstrate the importance of mitochondrial decline in the development of aneurysms, we generated a conditional mouse model with mitochondrial dysfunction specifically in vascular smooth muscle cells (VSMC) by conditional depleting Tfam (mitochondrial transcription factor A; Myh11-CreERT2Tfamflox/flox mice). We used a mouse model of MFS to test for drugs that can revert aortic disease by enhancing Tfam levels and mitochondrial respiration. RESULTS: The main canonical pathways highlighted in the transcriptomic analysis in aortas from Fbn1c1039g/+ mice were those related to metabolic function, such as mitochondrial dysfunction. Mitochondrial complexes, whose transcription depends on Tfam and mitochondrial DNA content, were reduced in aortas from young Fbn1c1039g/+ mice. In vitro experiments in Fbn1-silenced VSMCs presented increased lactate production and decreased oxygen consumption. Similar results were found in MFS patients. VSMCs seeded in matrices produced by Fbn1-deficient VSMCs undergo mitochondrial dysfunction. Conditional Tfam-deficient VSMC mice lose their contractile capacity, showed aortic aneurysms, and died prematurely. Restoring mitochondrial metabolism with the NAD precursor nicotinamide riboside rapidly reverses aortic aneurysm in Fbn1c1039g/+ mice. CONCLUSIONS: Mitochondrial function of VSMCs is controlled by the extracellular matrix and drives the development of aortic aneurysm in Marfan syndrome. Targeting vascular metabolism is a new available therapeutic strategy for managing aortic aneurysms associated with genetic disorders.

Differential survival throughout the full annual cycle of a migratory bird presents a life-history trade-off.

Long-distance migrations are among the most physically demanding feats animals perform. Understanding the potential costs and benefits of such behaviour is a fundamental question in ecology and evolution. A hypothetical cost of migration should be outweighed by higher productivity and/or higher annual survival, but few studies on migratory species have been able to directly quantify patterns of survival throughout the full annual cycle and across the majority of a species' range. Here, we use telemetry data from 220 migratory Egyptian vultures Neophron percnopterus, tracked for 3,186 bird months and across approximately 70% of the species' global distribution, to test for differences in survival throughout the annual cycle. We estimated monthly survival probability relative to migration and latitude using a multi-event capture-recapture model in a Bayesian framework that accounted for age, origin, subpopulation and the uncertainty of classifying fates from tracking data. We found lower survival during migration compared to stationary periods (ß = -0.816; 95% credible interval: -1.290 to -0.318) and higher survival on non-breeding grounds at southern latitudes (<25°N; ß = 0.664; 0.076-1.319) compared to on breeding grounds. Survival was also higher for individuals originating from Western Europe (ß = 0.664; 0.110-1.330) as compared to further east in Europe and Asia, and improved with age (ß = 0.030; 0.020-0.042). Anthropogenic mortalities accounted for half of the mortalities with a known cause and occurred mainly in northern latitudes. Many juveniles drowned in the Mediterranean Sea on their first autumn migration while there were few confirmed mortalities in the Sahara Desert, indicating that migration barriers are likely species-specific. Our study advances the understanding of important fitness trade-offs associated with long-distance migration. We conclude that there is lower survival associated with migration, but that this may be offset by higher non-breeding survival at lower latitudes. We found more human-caused mortality farther north, and suggest that increasing anthropogenic mortality could disrupt the delicate migration trade-off balance. Research to investigate further potential benefits of migration (e.g. differential productivity across latitudes) could clarify how migration evolved and how migrants may persist in a rapidly changing world.

Clinical features, damage accrual, and survival in patients with familial systemic lupus erythematosus: data from a multi-ethnic, multinational Latin American lupus cohort.

OBJECTIVES: This study aimed to compare the clinical features, damage accrual, and survival of patients with familial and sporadic systemic lupus erythematosus (SLE). METHODS: A multi-ethnic, multinational Latin American SLE cohort was studied. Familial lupus was defined as patients with a first-degree SLE relative; these relatives were interviewed in person or by telephone. Clinical variables, disease activity, damage, and mortality were compared. Odds ratios (OR) and 95% confidence intervals (CI) were estimated. Hazard ratios (HR) were calculated using Cox proportional hazard adjusted for potential confounders for time to damage and mortality. RESULTS: A total of 66 (5.6%) patients had familial lupus, and 1110 (94.4%) had sporadic lupus. Both groups were predominantly female, of comparable age, and of similar ethnic distribution. Discoid lupus (OR = 1.97; 95% CI 1.08-3.60) and neurologic disorder (OR = 1.65; 95% CI 1.00-2.73) were significantly associated with familial SLE; pericarditis was negatively associated (OR = 0.35; 95% CI 0.14-0.87). The SLE Disease Activity Index and Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) were similar in both groups, although the neuropsychiatric (45.4% vs. 33.5%; p = 0.04) and musculoskeletal (6.1% vs. 1.9%; p = 0.02) domains of the SDI were more frequent in familial lupus. They were not retained in the Cox models (by domains). Familial lupus was not significantly associated with damage accrual (HR = 0.69; 95% CI 0.30-1.55) or mortality (HR = 1.23; 95% CI 0.26-4.81). CONCLUSION: Familial SLE is not characterized by a more severe form of disease than sporadic lupus. We also observed that familial SLE has a higher frequency of discoid lupus and neurologic manifestations and a lower frequency of pericarditis.

Decline and recovery of a large carnivore: environmental change and long-term trends in an endangered brown bear population.

Understanding what factors drive fluctuations in the abundance of endangered species is a difficult ecological problem but a major requirement to attain effective management and conservation success. The ecological traits of large mammals make this task even more complicated, calling for integrative approaches. We develop a framework combining individual-based modelling and statistical inference to assess alternative hypotheses on brown bear dynamics in the Cantabrian range (Iberian Peninsula). Models including the effect of environmental factors on mortality rates were able to reproduce three decades of variation in the number of females with cubs of the year (Fcoy), including the decline that put the population close to extinction in the mid-nineties, and the following increase in brown bear numbers. This external effect prevailed over density-dependent mechanisms (sexually selected infanticide and female reproductive suppression), with a major impact of climate driven changes in resource availability and a secondary role of changes in human pressure. Predicted changes in population structure revealed a nonlinear relationship between total abundance and the number of Fcoy, highlighting the risk of simple projections based on indirect abundance indices. This study demonstrates the advantages of integrative, mechanistic approaches and provides a widely applicable framework to improve our understanding of wildlife dynamics.

Giant Aneurysm of the Interatrial Septum: A Multidisciplinary Approach.

A 46-year-old woman presented for a routine echocardiogram, which revealed a giant atrial septal aneurysm (ASA) with an atrial septal defect (ASD). We surgically excised the ASA and closed the ASD with a pericardial patch. ASA, although rare, poses embolic risks, thus necessitating closure when associated with shunts. Optimal stroke prevention remains uncertain.

ihtObtura: A novel liquid embolic agent with post-embolization radiopacity loss, in endovascular treatment of brain arteriovenous malformations, dural arteriovenous fistulas, and tumors: CLARIDAD trial.

BACKGROUND: Endovascular embolization is frequently used for vascular lesions of the head and neck. Newer agents may help to enhance visualization and improve treatment outcomes. METHODS: The CLARIDAD clinical trial was a prospective, single center, first-in-man investigation of neurovascular embolization using the novel embolic agent ihtObtura for a broad indication, covering the need for a liquid embolic agent in head and neck procedures. The primary outcomes assessed were therapeutic efficacy to deliver ihtObtura to embolize the catheterized pedicle and associated angiographic vascularity, and subsequent loss of radiopacity. Safety endpoints included procedural adverse events, modified Rankin Scale (mRS) score, morbidity, and mortality. Radiologic and clinical follow-up evaluations were conducted at 30, 90, 180 days, and 1 year post-treatment. RESULTS: 65 consecutive patients (mean age 37.8 years, 50.8% women) were treated over 129 sessions. A total of 42 brain arteriovenous malformations (AVMs; 90% grades III and IV), 8 dural arteriovenous fistulas (DAVFs), and 15 hypervascular tumors were treated with ihtObtura using an average of 3.9 mL per session and 7.7 mL per patient. We achieved therapeutic effectiveness in 99% of catheterizations. Radiopacity loss was complete after 74.3% of the sessions at 30 days, 95.6% at 90 days, and 100% at the 1 year follow-up. Serious adverse events (mRS score >2) occurred in two patients (3.1%) with previously ruptured high grade AVMs leading to one death and one permanent disabling morbidity. CONCLUSIONS: The study showed that ihtObtura was a novel, safe, and effective liquid embolic agent for the treatment of AVMs, DAVFs, and hypervascular tumors. Its key property of significant radiopacity loss contributes to improve anatomical understanding, particularly in staged procedures, as well as reduction in post-procedural imaging artifact. There may be additional benefits of eliminating tantalum from the embolic mixture in terms of lesion penetration.

Non-invasive surveillance of shared pathogens in the Eurasian brown bear (Ursus arctos) human interface.

Multi-host communities are perfect scenarios for the emergence and spread of pathogens, threatening the recovery of endangered, isolated, or inbred populations, such as the brown bear (Ursus arctos) in northwestern Spain. The population recovery in recent years has forced bears to occupy highly anthropized areas, increasing their interaction with human and domestic animals, with potential consequences for global health. During 2022-2023 a survey of parasites, bacteria and viruses shared between wildlife, domestic animals and humans was performed in this population using non-invasive surveillance, i.e., bear fecal samples (n = 73) and sponge-based sampling of trees (n = 42; 14 rubbed trees and 28 control trees). Pathogen detection rates were defined as the percentage of qPCR or culture-positive samples. Generalized linear models were fitted to assess their relationship with environmental variables including dispersion of the human population, and percentage of agricultural and periurban habitats in a 6 km-buffer around each sample. Canine Adenovirus type 1 (45.2%), Giardia spp. (15.1%), Salmonella spp. (12.3%), and extended-spectrum-beta-lactamases (ESBL) Escherichia coli (1.4%) were identified in fecal samples. In contrast, only five sponges from three rubbed and two control trees resulted positive to E. coli (14.3%). The results suggest that several pathogens are common in the Cantabrian brown bear population and that anthropization of the territory modulates their prevalence and richness. The effective design of management programs for bear conservation will require a one-health approach, in which genetic analysis of non-invasive samples can be key tools for the sanitary surveillance at the wildlife-livestock-human interface.

Extended septal myectomy versus alcohol septal ablation: clinical results at a national referral centre.

OBJECTIVES: Extended septal myectomy and alcohol septal ablation are 2 invasive treatments for hypertrophic obstructive cardiomyopathy. Our goal was to compare which of these techniques achieved a higher reduction in gradients, improvement in New York Heart Association (NYHA) functional class and reduction in medical treatment. METHODS: It is a single-centre observational and retrospective analysis. We used multivariable regression analyses to assess the association of ablation/myectomy with different outcomes. The odds ratio or coefficient along with the 95% confidence interval was estimated according to the group and adjusted for the corresponding preprocedural variables and EuroSCORE II. RESULTS: A total of 78 patients underwent septal myectomy, and 25 patients underwent alcohol septal ablation. Basal and Valsalva gradients after myectomy were reduced to a higher degree in comparison to ablation: 21.0 mmHg [P < 0.001, 95% confidence interval -30.7; -11.3], and 34.3 mmHg (P < 0.001, -49.1; -19.5) respectively. Those patients who received a myectomy had a lower probability of having moderate mitral regurgitation (odds ratio = 0.18, P = 0.054). Patients after septal myectomy were more likely to be NYHA functional class I (80.4%), whereas patients after ablation were more likely to be NYHA functional class III (48%). Both groups continued with beta-blocker therapy, but disopyramide could be discontinued after the myectomy in more cases (20%-36% vs 59%-1.3%; P < 0.001), and there was a tendency to discontinue calcium channel blockers (48%-16% vs 15.4-3.8%; P = 0.054). CONCLUSIONS: After adjustment using preprocedural gradients and EuroSCORE II, myectomy achieves greater reduction in left ventricular outflow tract gradients compared to septal ablation.

Endovascular treatment of distal internal carotid artery occlusions with retrievable stents.

BACKGROUND: Acute stroke due to distal intracranial internal carotid artery (ICA) occlusion has a poor natural history. Outcome in patients who receive intravenous tissue plasminogen activator (tPA) is also unsatisfactory. The objective of this study is to evaluate the effectiveness and safety of endovascular treatment with retrievable stents in these patients. METHODS: Data from a prospective register of patients with acute stroke treated with an endovascular procedure in a single centre were analysed. RESULTS: A total of 20 patients with distal ICA occlusion were collected. Mean baseline National Institutes of Health Stroke Scale score was 18. Eight cases (40%) had received previous intravenous tPA. Mean time from stroke to recanalization was 393 min. Retrievable stents with proximal occlusion and aspiration were used in all cases. In 3 patients, 2 retrievable stents were used simultaneously. Complete recanalization (thrombolysis in cerebral infarction 2b/3) was accomplished in 85% of cases. A favourable clinical outcome (modified Rankin Scale score 0-2) was achieved in 13 patients (65%). Mortality occurred in 2 cases (10%). CONCLUSIONS: Endovascular treatment of patients with distal ICA occlusion seems safe and effective. Retrievable stents may be the treatment of choice, although randomized clinical trials are necessary. The use of 2 retrievable stents at the same time could be an alternative technique useful in thrombi of larger size.

Increased Number of Passes and Double Stent Retriever Technique Induces Cumulative Injury on Arterial Wall After Mechanical Thrombectomy in a Swine Model.

The number of stentriever passes during endovascular thrombectomy impacts clinical outcomes in acute ischemic stroke. Previous studies suggest that the simultaneous double stent retriever technique (DSRT) could improve the efficacy and reduce the number of passes. We aim to analyze the degree of vessel wall injury according to the number of passes and technique (single vs. simultaneous devices). Histological changes were evaluated in renal arteries (RAs) of swine models after thrombectomy (1, 2, or 3 passes) with single stent (SSRT) and DSRT. Thrombectomy passes were performed in 12 RA: 3 samples from each artery were studied by optical microscopy to assess a vascular damage score. All thirty-six samples showed endothelial denudation and different degrees of damage in the deepest layers of the arterial wall; however, all arteries remained patent by the time of assessment. In all cases, the degree of vascular injury increased with the number of passes. Compared with a SSRT, DSRT showed a higher severity of histological damage corresponding to the damage caused by 1.4 SSRT passes. However, in distal arteries, vascular damage was relatively similar when comparing SSRT with multiple passes and DSRT with one pass. The degree of vessel injury increases with the number of passes. Even though histological damage per pass was 1.4 higher with DSRT than SSRT, short-term vessel patency was not compromised after up to 3 DSRT passes. Further studies are needed to characterize the risk-benefit ratio of the DSRT in routine clinical practice.

Hemolytic Anemia After an Aortic Dissection Treated With a Valve-Sparing Aortic Root Replacement.

A 46-year-old man with a personal history of a repaired aortic dissection was admitted because of hemolytic anemia. The transesophageal echocardiogram displayed an accelerated flow and a residual intimal flap in the proximal descending aorta. A total arch replacement was performed, the flap was removed, and his hemolytic anemia was resolved. (Level of Difficulty: Advanced.).

Risk of Infective Endocarditis Associated with Transcatheter Aortic Valve Implantation versus Surgical Aortic Valve Replacement: A Propensity Score-Based Analysis.

Background: Infective endocarditis (IE) is a feared complication after surgical aortic valve replacement (SAVR)/transcatheter aortic valve implantation (TAVI). It is not certain which procedure carries a higher risk. Our aim was to assess the risk of IE after SAVR/TAVI. Methods: We conducted an observational study of a prospective cohort, including patients with TAVI/SAVR, from March 2015 to December 2020. IE was defined according to the modified Duke's criteria. IE occurring during the first 12 months of the procedure was considered early IE, and an episode occurring after 12 months was considered late IE. The propensity score was designed to include variables previously associated with TAVI/SAVR and IE. An inverse probability of treatment weight was generated. Results: In total, 355 SAVR and 278 TAVI were included. Median follow-up, 38 vs. 41 months, p = 0.550. IE occurred in 5 SAVR (1.41%, 95% CI 0.2−2.6) vs. 13 TAVI (4.65%, 95% CI 2.2−7.2), p = 0.016. TAVI patients had more frequent early IE (3.2% vs. 0.3%, p = 0.006). In the PS analyses, IE risk did not differ: OR 0.65, 95% CI 0.32−1.32. Factors associated with TAVI IE included younger age (74y vs. 83y, p = 0.030), complicated diabetes mellitus (38.5% vs. 6.8%, p = 0.002), COPD (46.2% vs. 16.3%, p = 0.015), advanced heart failure (100% vs. 52.9%, p < 0.001), and peripheral arteriopathy (61.5% vs. 26.7%, p = 0.011). Conclusions: Early IE was higher with TAVI, but in the PS analyses, the risk attributable to each procedure was similar. Studies are needed to identify and optimize the risk factors of IE prior to TAVI.

Durable ventricular assist device in Spain (2007-2020). First report of the REGALAD registry.

INTRODUCTION AND OBJECTIVES: This report presents the clinical characteristics, outcomes and complications of all consecutive patients implanted with a long-term mechanical circulatory support device in Spain between 2007 and 2020. METHODS: Analysis of the Spanish Registry of durable ventricular assist devices (REGALAD) including data form Spanish centers with a mechanical circulatory support program. RESULTS: During the study period, 263 ventricular assist devices were implanted in 22 hospitals. The implanted device was an isolated continuous-flow left ventricular assist device in 182 patients (69%), a pulsatile-flow device (58 isolated left ventricular and 21 biventricular) in 79 (30%), and a total artificial heart in 2 patients (1%). The strategy of the implant was as bridge to heart transplant in 78 patients (30%), bridge to candidacy in 110 (42%), bridge to recovery in 3 (1%) and destination therapy in 72 patients (27%). Overall survival at 6, 12 and 24 months was 79%, 74% and 69%, respectively, and was better in continuous-flow left ventricular assist devices (84%, 80%, and 75%). The main adverse events related to this therapy were infections (37% of patients), bleeding (35%), neurological (29%), and device malfunction (17%). CONCLUSIONS: Durable ventricular assist devices have emerged in Spain in the last few years as a useful therapy for patients with advanced heart failure. As in other international registries, the current trend is to use continuous-flow intracorporeal left ventricular devices, which are associated with better results. Adverse events continue to be frequent and severe.

Normal perfusion pressure breakthrough phenomenon: what still remains unknown.

We report two cases of normal perfusion pressure breakthrough phenomenon after total brain arteriovenous malformation removal. Hereby, we demonstrate that not only autoregulation impairment in the ipsilateral hemisphere occurs but also contralateral remote vessels response does. Such findings may be observed at 2-4 weeks and may resolve after 1-3 months.

A papillary fibroelastoma with myxoma camouflage: a case report.

Background: Benign cardiac tumours are infrequent in clinical practice and, of these, cardiac myxoma is the one with the highest incidence. Given that a left intraventricular presentation is rare, other differential diagnoses such as papillary fibroelastoma should be considered. Case summary: A 73-year-old woman patient with cardiac mass detected in transthoracic echocardiography (TTE) after a transient ischaemic attack. At TTE 2D-3D, a left intraventricular mass anchored at the level of the anterolateral papillary muscle was detected. Subsequently, cardiac magnetic resonance (CMR) was performed for mass characterization. This revealed behaviour in T1 (isointense with respect to myocardium), T2 (hyperintense), very prolonged T1-mapping (1848 msg), and T2-mapping (161 msg) values, without gadolinium uptake in the first-pass perfusion sequence, but with intense uptake in late enhancement sequences. Previous findings were compatible with a diagnosis of papillary fibroelastoma. The mass was resected intraoperatively and, although its macroscopic appearance pointed to a diagnosis of cardiac myxoma, it was finally confirmed to be a papillary fibroelastoma by pathological anatomy. Discussion: In cases where the size of the mass and its mobility allow tissue characterization by CMR, a diagnosis of papillary fibroelastoma and its differentiation with cardiac myxoma are feasible by this cardiac imaging technique.

4D-Flow Cardiac Magnetic Resonance Imaging in Chronic Aortic Dissection Assessment: A Powerful Qualiquantitative Diagnostic Tool.

4-dimensional-flow cardiac magnetic resonance in patients with aortic dissection in chronic/post repair phase as a complementary diagnostic tool for anatomic-functional evaluation. Quali-quantitative analysis of 3 patients with this pathology clearly showing the true/false lumen, quantitative flow in false lumen, and helping in discerning lumen origin from different arterial vessels. (Level of Difficulty: Advanced.).

Patterns and determinants of dispersal in grey wolves (Canis lupus).

Dispersal is a key demographic process involving three stages: emigration, transience and settlement; each of which is influenced by individual, social and environmental determinants. An integrated understanding of species dispersal is essential for demographic modelling and conservation planning. Here, we review the dispersal patterns and determinants documented in the scientific literature for the grey wolf (Canis lupus) across its distribution range. We showed a surprisingly high variability within and among study areas on all dispersal parameters - dispersal rate, direction, distance, duration and success. We found that such large variability is due to multiple individual, social and environmental determinants, but also due to previously overlooked methodological research issues. We revealed a potential non-linear relationship between dispersal rate and population density, with dispersal rate higher at both ends of the gradient of population density. We found that human-caused mortality reduces distance, duration and success of dispersal events. Furthermore, dispersers avoid interaction with humans, and highly exposed areas like agricultural lands hamper population connectivity in many cases. We identified numerous methodological research problems that make it difficult to obtain robust estimates of dispersal parameters and robust inferences on dispersal patterns and their determinants. In particular, analyses where confounding factors were not accounted for led to substantial knowledge gaps on all aspects of dispersal in an otherwise much-studied species. Our understanding of wolf biology and management would significantly benefit if wolf dispersal studies reported the results and possible factors affecting wolf dispersal more transparently.

Loss of Mitochondrial Genetic Diversity despite Population Growth: The Legacy of Past Wolf Population Declines.

Gray wolves (Canis lupus) in the Iberian Peninsula declined substantially in both range and population size in the last few centuries due to human persecution and habitat fragmentation. However, unlike many other western European populations, gray wolves never went extinct in Iberia. Since the minimum number was recorded around 1970, their numbers have significantly increased and then stabilized in recent decades. We analyzed mitochondrial genomes from 54 historical specimens of Iberian wolves from across their historical range using ancient DNA methods. We compared historical and current mitochondrial diversity in Iberian wolves at the 5' end of the control region (n = 17 and 27) and the whole mitochondrial genome excluding the control region (n = 19 and 29). Despite an increase in population size since the 1970s, genetic diversity declined. We identified 10 whole mitochondrial DNA haplotypes in 19 historical specimens, whereas only six of them were observed in 29 modern Iberian wolves. Moreover, a haplotype that was restricted to the southern part of the distribution has gone extinct. Our results illustrate a lag between demographic and genetic diversity changes, and show that after severe population declines, genetic diversity can continue to be lost in stable or even expanding populations. This suggests that such populations may be of conservation concern even after their demographic trajectory has been reversed.