Space use, habitat selection and browsing effects of red deer in Sardinia

Sardinian deer increase feeding diversity within sheltering vegetation in a fragmented Mediterranean landscape

This study was carried out to investigate the feeding behavior of Sardinian deer roaming within a site of community interest (SCI, ITB042250), on Sardinian Island (39° 51' N 8° 45' E). Crop fields bordering the natural environment (wood forest and Mediterranean macchia, where the reserve of Sardinian deer partly overlaps) were monitored and turned into a living lab. The interest on wildlife-related crop damage poses a significant economic challenge, while anthropogenic pressures, such as urbanization and agricultural practices, increasingly impact wildlife by limiting habitat, feeding source diversity and access, and space distribution. In view of this, dietary habits of a group of 25 Sardinian deer (Cervus elaphus corsicanus Erxleben, 1777) were studied over an area of 45 hectares, in spring and autumn over two consecutive years. Within six representative sites (habitats) of investigation (SOI = 3 ha), two transects of 20 × 10 m per SOI, amounting to 240 m², served as parts of these sites, respectively, and were analyzed as to floristic composition and dominating plants. The number of freshly browsed/grazed plants by missing shoots was counted and assumed as signs of foraging activity of the Sardinian deer. The evenness of the dietary preference per habitat was calculated with the number of missing shoots and the number of plant species selected. The Mediterranean macchia accounted for the highest species (n = 76); crop field the fewest species (n = 19). Plants showing foraging signs by Sardinian deer ranged between n. 5 out of 46 species (10.9%) in the fallow and n. 6 out of 19 species (31.6%) in the crop field. Complementary feeding based on the availability of floristic diversity revealed to align to the typical foraging behavior of intermediate feeder in all SOIs: the higher the species, the higher the number of foraged species (ρ = 0.86). Sardinian deer foraged on n. 35 out of 129 plant species present (27.1%) within the whole transect area. Data highlight two feeding behavior: 1)high evenness-feeding (less foraging on high number of plant species, respectively: fallow, crop field, macchia border); 2) low evenness-feeding (large foraging on few species, Avena or Cytisus: field, bordering both macchia and fallow, macchia).The Sardinian deer fed on every SOI, with highest consumption in the macchia and least in oat open field. The feeding behavior of Sardinian deer confirms the ability to adapt to the varying vegetation in each habitat, respectively, by seeking energy and nutrients on the one hand and shelter on the other, by limiting the preference for crop field center.

Differences in the Diets of Female and Male Red Deer: The Meaning for Sexual Segregation

Sexual segregation is a common phenomenon among animals, particularly dimorphic ones. Although widely addressed, the reasons and consequences of sexual segregation are still an important topic in need of better understanding. In this study, we mainly evaluate the diet composition and feeding behaviour of animals, which are related to the use of different habitats by the sexes, a special case of sexual segregation also termed habitat segregation. Sexually size dimorphic males and females often have different energetic and nutritional needs and, thus, different diets. We collected fresh faecal samples from wild Iberian red deer (Cervus elaphus L.) in Portugal. Samples were analysed in terms of diet composition and quality. As expected, both sexes differed in their diet composition, with males eating more arboreous species than females, but this difference was affected by sampling periods. Diet composition of both sexes had the biggest differences (and the lowest overlap) in spring, which corresponds to the end of gestation and beginning of birth. These differences might be a consequence of the sexual body size dimorphism characteristic of this species, as well as of different needs due to different reproductive costs. No differences regarding the quality of the excreted diet were observed. Our results may help to understand some patterns of sexual segregation observed in this red deer population. However, besides foraging ecology, other factors may also be contributing to sexual segregation in this Mediterranean population of red deer, and further studies focusing on sexual differences regarding feeding behaviour and digestibility are needed.

Reintroductions of the Corsican Red Deer (Cervus elaphus corsicanus): Conservation Projects and Sanitary Risk

The Corsican red deer is an endangered subspecies that needs artificial translocation projects to gain its complete recovery with the formation of viable, interconnected populations. Between 2007 and 2017, we performed two reintroduction projects in four sites in central–eastern Sardinia via tracking 32 deer by means of GPS/GSM radiotelemetry. On the basis of the obtained results, we built a species distribution model (SDM) using MaxEnt software, selecting 200 random points from the merged deer core areas as presence data. Furthermore, to evaluate the sanitary risk linked to artificial translocations, we analyzed deer positivity to Bluetongue virus (BTV) in the founder populations. The SDM showed a high deer capability to colonize central–eastern Sardinia, but it also showed the possibility of spreading BTV to domestic sheep because sanitary analyses confirmed the virus’ presence in the founder populations. Our main conclusion was that reintroductions are effective tools for the long-term conservation of the Corsican red deer, as long as sanitary risks are minimized by means of sanitary monitoring of translocated deer.

The spatial ecology of red deer under different land use and management scenarios: Protected areas, mixed farms and fenced hunting estates

The knowledge regarding the spatial ecology of red deer (Cervus elaphus) in different environments is crucial if effective management actions are to be designed. However, this knowledge continues to be scarce in the complex contexts of mixed land use and management circumstances. This study describes the spatial ecology of red deer monitored using GPS collars in Mediterranean ecosystems of South-Central Spain, considering the effect of individual and seasonal (food shortage period, rut, hunting season and food abundance period) factors on different land use and management scenarios, namely protected areas, mixed farms and fenced hunting estates. Our results showed less activity (ACT), a shorter daily range (DR) and a smaller home range (HR) during the food shortage period: ACT: 0.38 ± (SD) 0.12; DR: 3010.9 ± 727.3 m; and weekly HR: 122.2 ± 59.6 ha. With regard to land use, individuals were less ACT and had a smaller DR on fenced hunting estates (ACT: 0.24 ± 0.12; DR: 1946.3 ± 706.7 m) than in protected areas (ACT: 0.59 ± 0.12; DR: 4071.4 ± 1068.2 m) or on mixed farms (ACT: 0.57 ± 0.29; DR: 5431.1 ± 1939.5 m) in all the periods studied. Red deer selected land cover with forage and shelter when foraging and resting, respectively. When drive hunt events occurred (mixed farms and fenced hunting estates), the deer were more prone to select safer habitats (scrublands) and avoid open areas (crops or grasslands) than were their counterparts in protected areas. The patterns observed can be explained by sexual and seasonal differences as regards requirements, the response to disturbances and, interestingly, population management. Our results provide useful information with which to design scientifically-based species adaptive management in response to relevant and timely situations in Europe, such as the potential transmission of shared infections, vehicle collisions, and damage to crops and ecosystems.

Effect of leaf type on browse selection by free-ranging goats in a southern African savanna

Broad- and fine-leaved woody species respond to seasonal changes from wet to dry season differently. For example, broad-leaved species shed their leaves earlier, while fine-leaved species, especially acacias retain green foliage well into the dry season. These differences are expected to result in variation in selection of broad- and fine-leaved woody species as browse by free-ranging goats. We tested the hypothesis that free-ranging goats select broad-leaved woody species more than fine-leaved species during wet (growth) season and fine-leaved woody species more than broad-leaved species during dry season. In addition, we tested if broad- and fine-leaved woody species had different foliar dry matter digestibility and chemical composition (crude protein, neutral detergent fibre, acid detergent fibre, total phenolics and condensed tannins concentration). Free-ranging goats were observed foraging on broad- and fine-leaved woody species over a two-year period (2014 and 2015) during three seasons: early wet (October/November), late wet (February/March) and dry (May/June). Ivlev's selectivity or Jacob's index (Ei) was calculated for five woody species (two broad-leaved and three fine-leaved) browsed by goats during wet and dry season. Jacob's selectivity index was higher for broad-leaved (Ziziphus mucronata and Searsia (Rhus) tenuinervis) than fine-leaved woody species (Acacia nilotica, Acacia karroo and Dichrostachys cinerea) during wet season. However, the trend was reversed during dry season with fine-leaved species having higher Jacob's selectivity index than broad-leaved species. Leaf dry matter digestibility and chemical composition was similar between broad- and fine-leaved woody species throughout the year. We conclude that goats selected broad-leaved woody species during wet season when browse was plentiful and then switched to fine-leaved species which retained leaves during dry season.

Historical Suitability and Sustainability of Sicani Mountains Landscape (Western Sicily): An Integrated Approach of Phytosociology and Archaeobotany

Since 2015, the ongoing project “Harvesting Memories” has been focused on long-term landscape dynamics in Sicani Mountains (Western Sicily). Archaeological excavations in the case study site of Contrada Castro (Corleone) have investigated a settlement which was mainly occupied during the Early Middle Ages (late 8th–11th century AD). This paper aims to understand the historical suitability and sustainability of this area analysing the correlation between the current dynamics of plant communities and the historical use of woods detected by the archaeobotanical record. An integrated approach between phytosociology and archaeobotany has been applied. The vegetation series of the study area has been used as a model to understand the ecological meaning and spatial distribution of archaeobotanical data on charcoals from the Medieval layers of the Contrada Castro site. The intersection between the frequency data of the archaeobotanical record and the phytosociological analysis have confirmed the maintenance of the same plant communities during the last millennium due to the sustainable exploitation of wood resources. An integrated comparison between the structure and composition of current phytocoenoses with archaeobotanical data allowed us to confirm that this landscape is High Nature Value (HNV) farmland and to interpret the historical vegetation dynamics linked to the activities and economy of a rural community.

Farmed red deer home range, habitat use and daily movement patterns in a Southland, New Zealand, tussock grassland over calving and lactation

Considerable expansion of red deer farming has occurred in the South Island high country of New Zealand. On these farms, breeding hinds are usually continuously grazed (set-stocked) at low population densities in large highly modified native-tussock grassland paddocks during their calving and lactation seasons. The present study determined how these hinds use the tussock grassland over this critical period, identifying the most essential resources for them and also some potential long-term consequences of their behaviour on the grassland ecosystem. This was achieved by tracking nine GPS-collared hinds over 2 years on a high-country deer farm in Te Anau, Southland, New Zealand. The home ranges of the GPS-tracked hinds varied widely, occupying between 15% and 52% of the total paddock area. Vegetation dominated by naturalised exotic pasture species covered the greatest proportion (>60%) of eight of nine hind home ranges. In contrast, tussock-dominant vegetation coverage was far more variable (0.4–46%), with several indicators suggesting that this vegetation type was used as a substitute for pasture areas under high intra-specific competition among the deer. Both pasture- and tussock-dominant vegetation was used in proportion to its availability. In contrast, shrub-dominated vegetation was used less than its proportional availability, indicating that it was not being put under as much foraging or grazing pressure. This has implications for the further ingression of this vegetation type over time. There was also clear evidence that certain paddock topography was being favoured by the hinds, namely steeper and higher-altitude areas of a paddock. On the basis of these findings, some potential methods for aiding in the management of these extensive tussock grassland paddocks under deer grazing are suggested.

At home in a new range: wild red deer in south-eastern Queensland

Context Wild deer are increasing worldwide and, in Australia, prompting land managers to review management strategies. Management activities may be ineffective without a sound understanding of the ecology of the species. No peer-reviewed research has been published for wild red deer in Australia, where they have been introduced. Aims To help land managers gain an understanding of some movement parameters of introduced wild red deer out of their natural range. Methods GPS collars were used to obtain movement rates (m h–1), annual home range using three estimators and seasonal home range using the Local Convex Hull estimator. Key findings Deer at our study site displayed typical crepuscular movements. However, the lack of elevated activity for stags in summer varies greatly to reports from overseas. The annual home range of hinds was much smaller than that of stags. Large differences for seasonal home ranges from the same deer for two winters suggest that seasonal conditions may exert a large influence on the size of home ranges. The home ranges of deer at our study site were comparable with the largest reported in European studies, but the relationship between deer density and home-range area was markedly different. Conclusions It appears that Australian wild red deer behave differently from their European conspecifics for several important movement parameters. Wild stags did not display the high levels of movement activity in summer, like those in Europe, and the home-range areas of our deer were very large for the high densities we encountered compared with overseas reports. Implications Targeted management of hinds may prove beneficial as hinds had a much smaller and continuous home range than stags. If managers want to target stags, there is only a short rut period when they continually associate with hinds and that may be the most efficacious time for control. Additionally, future research may need to explore the link between home range and deer density, and the effect of variation in rainfall on home range and movement of wild red deer which may influence management activities more than do the regular seasonal patterns found in Europe.

Pitfalls in using counts of roaring stags to index red deer (Cervus elaphus) population size

Counting roaring stags during the rut has been proposed as a means to assess deer population size and trends but few, if any, attempts have been made to evaluate the reliability of this technique. By means of a commonly used field protocol, we assessed to what extent relative abundance estimates of red deer (Cervus elaphus) based on roaring-stag counts in the northern Apennines (Italy) were susceptible to exogenous and unpredictable sources of variability. By using up to 26 simultaneous observers in an area of 5218 ha, we estimated densities from 0.45 to 0.61 roaring stags per 100 ha in 3 consecutive years (1992–94), corresponding to annual changes in the number of counted roaring stags ranging from –21% to +35.7%. However, only in two of the three years were seasonal trends and peaks in roaring activity apparent, and timing of the survey was not always synchronous with the roaring peak. In addition, annual and nocturnal variation in roaring activity, and weather conditions during the survey, might have influenced the counts to some extent, probably determining high Type I and Type II error rates. We contend that additional sources of error, associated with unknown demographic and ecological settings, may further increase unreliability of the technique when it is used to estimate absolute density of red deer populations. We conclude by emphasising that managers should not use this method for population monitoring unless they can prove it can yield reliable results.