Welfare of Free-Roaming Horses: 70 Years of Experience with Konik Polski Breeding in Poland

To prevent abuse and to assure the welfare of domestic horses, attempts to assess welfare in a standardized way have been made. Welfare-assessment tools often refer to the physical and social environments of feral domestic horses as examples of welfare-friendly conditions for horses. However, free-roaming horses are often exposed to conditions or states that may be regarded as welfare threats or abuse. The aim of this review was to present cases of welfare compromises as well as natural ways to restore high standards of welfare to Konik polski horses (Koniks) living in semiferal conditions in a forest sanctuary over the course of 70 years. Welfare problems in Koniks related to feeding, locomotor, social, reproductive, and comfort behavior, as well as health issues concerning hoof trimming and parasitism in Koniks, are discussed. Periodic food scarcity or abundance, stressful events around weaning and gathering, the consequences of fights among stallions, exposure to sire aggression during dispersal, lameness during “self-trimming,” exposure to insect harassment, high levels of parasitism, and specific landscape formations may endanger free-roaming horses. It has to be underlined that despite the excellent adaptability of horses to free-roaming conditions, one should be aware that welfare problems are to be expected in any semiferal population. Here, we present the management system applied for 70 years in free-roaming Konik polski horses that minimizes welfare threats. It allows close follow-up of individual horses, the strict monitoring of health and welfare on a daily basis, and if necessary, instant reactions from caretakers in cases of emergency. Moreover, it addresses the problem of starvation due to overgrazing and thus, the ethical controversy related to the eradication of surplus animals causing environmental damage.

Behavioral, Physiological, Demographic and Ecological Impacts of Hematophagous and Endoparasitic Insects on an Arctic Ungulate

Animals that deliver a toxic secretion through a wound or to the body surface without a wound are considered venomous and toxungenous, respectively. Hematophagous insects, such as mosquitoes (Aedes spp.), meet the criteria for venomous, and some endoparasitic insects, such as warble flies (Hypoderma tarandi), satisfy the definition for toxungenous. The impacts of these insects on their hosts are wide ranging. In the Arctic, their primary host is the most abundant ungulate, the caribou (Rangifer tarandus). The most conspicuous impacts of these insects on caribou are behavioral. Caribou increase their movements during peak insect harassment, evading and running away from these parasites. These behavioral responses scale up to physiological effects as caribou move to less productive habitats to reduce harassment which increases energetic costs due to locomotion, reduces nutrient intake due to less time spent foraging, and can lead to poorer physiological condition. Reduced physiological condition can lead to lower reproductive output and even higher mortality rates, with the potential to ultimately affect caribou demographics. Caribou affect all trophic levels in the Arctic and the processes that connect them, thus altering caribou demographics could impact the ecology of the region. Broadening the definitions of venomous and toxungenous animals to include hematophagous and endoparasitic insects should not only generate productive collaborations among toxinologists and parasitologists, but will also lead to a deeper understanding of the ecology of toxic secretions and their widespread influence.

Evaluating trade-offs between forage, biting flies, and footing on habitat selection by wood bison (Bison bison athabascae)

Habitat selection is a behavioural process that ultimately affects animal fitness. Forage availability and predation risk are often studied in the context of habitat selection for large ungulates, while other biological and environmental factors such as insect harassment and footing are less studied. Here we examine trade-offs in summer habitat selection between forage availability for wood bison (Bison bison athabascae Rhoads, 1898) with that of biting-fly harassment and soil firmness, which affects activity budgets and predation risk, respectively, and contrast this to winter when flies are absent and soils frozen. Using path analysis, we demonstrate that graminoid availability was not related to habitat selection in summer, but was positively related to habitat selection in winter. Habitat selection in summer was negatively related to biting-fly abundance and positively related to firmer footing. Our results suggest that bison observe trade-offs in summer between maximizing forage intake and minimizing harassment from that of biting flies, while avoiding areas of soft substrates that affect locomotion and vulnerability to predators. In contrast, during the winter, bison focus on areas with greater graminoid availability. Although forage is a key aspect of habitat selection, our results illustrate the importance of considering direct and indirect effects of multiple biological and environmental factors related to ungulate habitat selection.

Keeping cool in the warming Arctic: thermoregulatory behaviour by Svalbard reindeer (Rangifer tarandus platyrhynchus)

In animals with long generation times, evolution of physiological and morphological traits may not be fast enough to keep up with rapid climate warming, but thermoregulatory behaviour can possibly serve as an important buffer mitigating warming effects. In this study, we investigated if the cold-adapted Svalbard reindeer (Rangifer tarandus platyrhynchus (Vrolik, 1829)) used cool bed sites as a thermoregulatory behaviour in the summer. We recorded habitat variables and ground temperature at 371 bed sites with random “control” sites 10 and 100 m distant. Using case-control logistic regression, we found that reindeer selected bed sites on cool substrates (snow and mire), as well as cold, dry ground on days with warm ambient temperatures, while they avoided such sites on cold days. Selection of both cool substrates and cool ground did not depend on age or sex. The study was conducted in an environment where neither predatory threat nor insect harassment influenced bed site selection. Our findings suggest that the thermal landscape is important for habitat selection of cold-adapted Arctic ungulates in summer. Thus, behavioural strategies may be important to mitigate effects of climate change, at least in the short term.

Estimates of caribou herd size using post-calving surveys in the Northwest Territories and Nunavut, Canada: A meta-analysis

Post-calving surveys to estimate herd size of barren-ground caribou (Rangifer tarandus groenlandicus, R. t. granti, and R. t. caribou) have been used for caribou herds in Alaska, Yukon, Northwest Territories, Nunavut, and Québec/Labrador. The main field procedure uses relocation of collared caribou to locate aggregated groups of hundreds or thousands of caribou during times of high insect harassment that usually occur in July. These groups are then pho­tographed to obtain a count of the caribou in the aggregated groups. Often some caribou are missed, and the count of caribou may be a negatively biased estimate of total herd size, unless a high proportion of the herd is found and photographed. To address this, some previous studies have used the Lincoln-Petersen estimator, which estimates the proportion of the herd counted based on the percentage of available collared caribou found during the survey. However, this estimator assumes equal probabilities of all groups of caribou being found, regardless of group size and the numbers of collared caribou in the group. These assumptions may not be valid, as larger groups are more likely to be found than smaller groups, particularly if there are several collared caribou present. This may lead to estimates that are biased low, along with an estimate of variance that may also be biased low. A two phase estimator developed by Rivest et al., in 1998 became available in R statistical software in 2012. We analyzed 20 data sets from post-calving surveys in the NWT and NU carried out between 2000 and 2015 using the Rivest estimator to explore working characteristics of this estimator. We compared the Rivest estimates with Lincoln-Petersen estimates and total counts on each survey. We considered factors that influence precision of the Rivest estimator with a focus on sampling factors such as the proportion of collars found, the number of collars available, and natural factors such as the degree of aggregation of caribou in each survey (as indexed by the negative binomial dispersion parameter). In general, the Rivest estimator displayed acceptable preci­sion when high proportions of caribou groups with collars were detected and counted, collar numbers were sufficient, and aggregation was adequate. Notable exceptions occurred in years of lower aggregation which resulted in many small groups with 0 or few collared caribou, and in these cases herd estimates had large variances and low precision. Estimates from the Rivest estimator, Lincoln-Petersen estimator, and total counts converged when sampling effort was high, collar numbers relative to herd size were high, and caribou were well aggregated in a limited number of groups. In other cases, estimates of the Rivest estimator were generally higher than Lincoln-Petersen estimates, presumably due to negative bias with the Lincoln-Petersen estimator. We provide a set of working recommendations to optimize field sampling to ensure reliable estimates of herd size using post-calving methods.

Reindeer 24-hr within and between group synchronicity in summer versus environmental variables

The impact of abiotic stimuli on the circadian activity rhythm of Rangifer has long been debated. Their highly gregarious and mobile behaviour presupposes synchronized behaviour within a group, while a predominant abiotic influence would be expected to synchronize separate, independent groups subjected to the same environment. We tested within and between group synchronization of semi-domestic reindeer during summer observing 6 independent groups located in close proximity to each other. We also tested how some external environmental factors affected the animals’ behaviour. Activity of all individuals (3 females in 6 groups, n = 18 reindeer) was recorded every 10 minutes 24-hrs a day, along with weather variables and biotic factors such as insect harassment. Data were divided into two periods of 8 and 6 days, respectively, separated by a period of 6 days. Animals within a group showed highly synchronized behaviour, reflected in overlapping periods of grazing and ruminating. There was little or no synchronization between groups, reflected by little or infrequent overlapping of activities amongst some of the groups. Rarely were all 6 groups active or inactive simultaneously. There was no consistent or significant influence on the reindeers’ behaviour by any of the environmental variables recorded. Thus, and as expected, in the absence of external environmental stimuli, the activity of individuals within a group was synchronized. However, there was no synchronization amongst independent groups. This supports the claim that during summer, in the absence of disturbance from stimuli such as insect harassment or anthropogenic activities, reindeer have a 24-hr polycyclic activity rhythm independent of climatic variables. Instead of abiotic factors, such as light, reindeers’ activity rhythms were defined by internal physiological processes and intra-specific group interactions reflected in almost complete within group synchronization and lack of between group synchronization. Abstract in Norwegian / Sammendrag: Betydningen av abiotiske variabler på reinens døgnrytme har lenge vært diskutert. Med sin gruppeadferd og mobilitet forventer man samhandling innenfor ei gruppe, mens abiotiske variabler faktorer forventes å synkronisere adferden mellom adskilte grupper i samme miljø. Vi testet adferdssynkroniseringen innenfor og mellom grupper av tamrein ved å observere aktiviteteter i seks uavhengige grupper hver med tre simler. Vi testet også hvordan noen miljøvariabler påvirker dyrenes adferd. Aktiviteten til alle individene ble observert hvert tiende minutt hele døgnet sammen med klimatiske forhold og biotiske variabler som insektplage. Dyrene innenfor ei gruppe viste klart felles adferd med samme beite- og liggeperioder. Det var lite eller ingen synkronisering mellom grupper, idet det var lite eller tilfeldig sammenfall av aktiviteter. Sjelden var alle seks gruppene aktive eller inaktive samtidig. Aktiviteten til individer innenfor en gruppe var synkronisert som forventet, uten eksterne miljøvariabler. Derimot var det ingen synkronisering mellom uavhengige grupper. Dette støtter teorien at reinsdyr har en 24-t polysyklisk aktivitetsrytme uavhengig av klimatiske variabler på sommeren og uten sterke påvirkninger utenfra som parasittiske insekter eller menneskelige aktiviteter. Vårt forsøk viste at reinens aktivitetsrytme tydeligvis var definert av interne fysiologiske prosesser og interaksjoner innen gruppen.

Insect avoidance may override human disturbances in reindeer habitat selection

Habitat selection of semi-domesticated reindeer (Rangifer tarandus tarandus) was investigated through faecal pellet- group counts and by direct observations of reindeer from helicopter in the Långfjället area in Idre reindeer herding district (62˚10’N) and in Mittådalen reindeer herding district (62˚50’N, aerial observations only). Reindeer pellets were found to be most abundant in habitats at high altitudes, and in some vegetation types. Pellet-group densities tended to be higher near the tourist trails, which often follow higher altitudes in the terrain. The aerial surveys showed that the reindeer moved towards higher altitudes when the wind speed was low and the temperature was high both in June and July. In June they moved towards lower regions when temperature was low and the wind speed was strong. The conclusion is that the reindeer use Långfjället to escape insect harassment and warm weather, even though disturbance by tourism sometimes is high.Abstract in Swedish / Sammanfattning:Habitatval hos tamren (Rangifer tarandus tarandus) undersöktes genom att göra en spillningsinventering och genom att göra flygobservationer från helikopter. Studien gjordes på Långfjället (62˚10’N) i Idre nya sameby och i Mittådalens samebys sommarbetesområde (62˚50’N, endast flygobservationer). På Långfjället finns det vandringsleder som är frekventerade av vandrare från juni månad fram till september. Spillningen visade att renarna föredrog höjderna i området samt en del av vegetationstyperna. Det var också mer spillning närmare vandringslederna. Detta kan förklaras av att vandringslederna följer höjderna i terrängen. Flyginventeringarna under både juni och juli visade att renarna rörde sig mot högre terräng när det var varmt och lugnt väder. I juni rörde dom sig också i lägre terräng när det var stark vind och kallt väder. Slutsatsen är att renarna väljer att vistas i högre terräng för att undvika störningar från insekter och för att finna svalka trots att det är mänsklig aktivitet i området.