Road impacts on the demography and movement of animal populations; optimising study designs and understanding the long-term consequences
Notice bibliographique
Résumé
Given the extent of the global road network, roads are considered one of the most pressing contemporary conservation issues. However, explicit understanding about how roads affect population dynamics, and so how to mitigate these effects, is limited. This thesis aimed to identify the optimal study designs for assessing population-level impacts of roads as well as to understand both animal survival and movements near roads. The west European hedgehog (Erinaceus europaeus), a priority species for conservation in the UK, is used as a case study. \n \nBetween May 2020 and November 2021, vertebrate road mortality was recorded using repeat, standardised road surveys in Nottinghamshire, UK, and analysed using novel equations, Generalised Linear Models (GLM), and Generalised Additive Models (GAM). Along the road survey route, four sites were repeatedly studied using spotlight surveys to quantify hedgehog population dynamics. Simultaneously, GPS-tracking of 127 hedgehogs across the Nottinghamshire sites and seven additional UK-wide sites took place. Road avoidance behaviour was analysed using GLMs and the ‘true’ risk of road mortality was analysed using a Resource Selection Function. \n \nAverage carcass persistence rates ranged between 0.69 and 6.00 days (average 3.10 days ±4.61 SD) and were driven by body mass and road type. Road mortality patterns tracked life history events and were predicted by a combination of road design, urbanity, and traffic volume. With greater densities, survival probabilities and reproductive rates, more urbanised local hedgehog populations appeared to compensate for road mortality. Eighty-four percent (n = 107) of hedgehogs exhibited significant road avoidance behaviour and road crossings showed variation by sex, road type, time of night, and season. Traffic volume and vehicle speed, especially on the outskirts of residential areas, were key components of the ‘true’ risk of road mortality, whilst intermediate roads produced the greatest annual road mortality probability. \n \nThis thesis provides researchers with robust methodology for the accurate interpretation of road mortality rates and their population-level impacts. In addition, this is the first study to establish local population differences in road mortality impacts in hedgehogs and that road mitigation should consider the potential presence of meta-population dynamics. The GPS data suggest that hedgehogs may be perceiving the risks and rewards of traversing road networks and adjusting their behaviour accordingly. Combining insight from the population and movement ecology, as adopted in this thesis, can ease the constraints surrounding decision-making for conservation planning and road mitigation.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,009 | 0,020 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,001 | 0,002 |
| Études des sciences et des technologies | 0,001 | 0,001 |
| Communication savante | 0,002 | 0,003 |
| Science ouverte | 0,001 | 0,002 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,007 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».