Scrub Areas Research Articles

Winter habitat preferences of feral American minkMustela vison in Biscay, Northern Iberian Peninsula

We studied correlates of habitat use of riparian feral American minkMustela vison Schreber, 1777 during winter in Biscay (Northern Iberian Peninsula). We live-trapped and radio-tagged 10 American mink (5 males and 5 females) and successfully radiotracked 7 of them (3 males and 4 females). During resting periods both sexes selected areas with dense scrub and near to deep waters. Both sexes used underground dens as well as resting sites located above the ground, but during cold days females rested in buildings much more often than males. Active females used areas of dense scrub, and males used large scrub patches. The results are interpreted in the light of mink hunting techniques and perceived predation risk: on larger scales, mink select areas primarily by food abundance, while on very small scales they use scrub and similar structures providing safe areas to hunt, forage and rest. The strong preference for banks with dense scrub provides options for management of the species.

Outbreak of scrub typhus in jammu — A report

Background: Jammu is scrub typhus prone. Scrub typhus is often seen when troops move out of permanent locations. Methods: In a prospective study cases of fever reporting to the local military hospital from July to October 2002 were examined clinically, investigated and categorised as scrub typhus when Weil Felix readings were above 1:160. Results: Twelve cases of scrub typhus were diagnosed during the period of study. The clinical features included fever, malaise and conjunctival congestion. However rashes were rare and only one had an eschar. Multisystem complications occurred in one patient. There was a spatial and temporal clustering of cases. Control of outbreak was carried out by 25% benzyl benzoate impregnation of clothing, clearing of scrub, residual spray with malathion and antirodent measures. Conclusion: Scrub typhus outbreaks have been noted whenever troops move out of permanent locations to scrub areas.

Behavioural profile during suckling period in Martina Franca breed jennies reared under semi-extensive conditions

Behavioural profiles of maintenance and social behaviours were studied in Martina Franca breed female donkey (jennies) during the period in which they had suckling foals (1 week to 6 months after foaling). The animals were reared in Southern Italy (40°37′N latitude) and were managed in husbandry conditions, with free access to a natural scrub area and sown pasture all year round. A total of 10 adult, pluriparous jennies, which had a similar foaling date were used. The behavioural observations in the jennies were performed in presence of their foals, for 120 daylight hours. A total of 14 activities were recorded using focal animal sampling (5 min intervals), including maintenance behaviours such as feeding, drinking, walking, resting, and a whole range of less conspicuous activities relative to eliminative and social behaviour such as olfactory communication, grooming, play and vocalisations. Meterological data were also recorded throughout the study. The results indicated that maintenance behaviours differed significantly as a function of the time since foaling (0.05 > P < 0.01). The effect of a.m. or p.m. hours of day were also significant (0.05 > P < 0.01), except for standing. All the activities included in maintenance behaviours were markedly influenced by the individual ( P < 0.01). Among the social ativities considered, the jennies showed a constant proportion of time spent grooming and there was a tendency for an increase in play between dams and their foals by the end of suckling period (4th–5th month). This study offers some information regarding quantitative behavioral profiles of jennies reared under domestic conditions during the suckling period.

Comparison of three devices for estimating fire temperatures in ecological studies

AbstractQuestions: Are calorimeters and pyrometers accurate and reliable for describing fire parameters in large‐scale ecological projects, and can data from them predict data derived from thermocouples? Do mechanical pre‐treatments in Florida scrub areas alter fire properties?Location: Lake Wales Ridge, Florida, USA.Methods: We deployed thermocouples attached to digital dataloggers, copper and lacquer paint pyrometers and aluminium can calorimeters filled with water in four areas of undisturbed Florida scrub and sandhill vegetation and in adjoining areas pre‐treated with logging, subcanopy felling or mowing. Individual dataloggers were positioned in areas spanning a range of vegetation structure; three calorimeters and three pyrometers were placed with each thermocouple. We also deployed individual calorimeter‐pyrometer pairs. Sites were burned, after which we compared methods for characterizing fire, particularly the ability of pyrometers and calorimeters to predict values derived from thermocouples.Results: Pyrometers best predicted peak 1‐minute mean temperatures and were least successful at estimating maximums. Calorimeters were associated with the number of minutes maximum temperatures exceeded 60 ßC, but were damaged at high residence times and inconsistent at low temperatures. Both pyrometers and calorimeters detected site and treatment differences in fire intensities. These analyses and logistic considerations give pyrometers an edge over calorimeters in situations where dataloggers are impractical. Mechanical pre‐treatments to fire altered fire parameters. Mowing reduced fire temperatures but had different effects on areas burned; this was related to the length of time elapsed between mowing and burning. Subcanopy felling increased both fire coverage and temperatures.Conclusion: Pyrometers outperformed calorimeters as a cheap method for describing relative temperature regimes that are a function of both temperature and residence time. Pyrometers were able to demonstrate how mechanical treatments applied prior to prescribed burning altered fire parameters. Pyrometers are a useful tool for investigating biological responses to fire at multiple scales and in heterogeneous vegetation.

Microhabitat use by Eligmodontia typus (Rodentia: Muridae) in the Monte Desert (Argentina)

Eligmodontia typus is widespread in southern Peru, western Bolivia, northern Chile, and all along the extent of the Andes mountains of Argentina, from the Salta province down to the Strait of Magellan (Redford and Eisenberg 1992). Typically, it inhabits open vegetation areas with high proportion of bare soil like Larrea flatlands, sandy lowland scrub areas, and sandy flats with halophytic plants (Mares 1975a, b; Redford and Eisenberg 1992). In the central Monte Desert, this species dominates sand dune habitats (Corbalan and Ojeda 2004), as well as open shrublands and disturbed grasslands of the Andean piedmont (Gonnet and Ojeda 1998). Ojeda (1989) demonstrated that in areas disturbed by fire, where vegetational complexity decrease, the population of this species increase. However, E. typus has been also reported as very abundant in dense shrublands dominated by Larrea cuneifolia, with high grass cover (Corbalan and Ojeda 2004). Using Beta-light, Thompson (1982) was able to demonstrate that the highly specialized rodents of the genus Dipodomys spend more time foraging near or beneath bushes, bounding rapidly across open areas, in contrast to results from earlier studies using live trapping. Eligmodontia typus shows a morphological similarity with the North American

Comparison of three devices for estimating fire temperatures in ecological studies

Questions Are calorimeters and pyrometers accurate and reliable for describing fire parameters in large-scale ecological projects, and can data from them predict data derived from thermocouples? Do mechanical pre-treatments in Florida scrub areas alter fire properties?Location: Lake Wales Ridge, Florida, USA.Methods: We deployed thermocouples attached to digital dataloggers, copper and lacquer paint pyrometers and aluminium can calorimeters filled with water in four areas of undisturbed Florida scrub and sandhill vegetation and in adjoining areas pre-treated with logging, subcanopy felling or mowing. Individual dataloggers were positioned in areas spanning a range of vegetation structure; three calorimeters and three pyrometers were placed with each thermocouple. We also deployed individual calorimeter-pyrometer pairs. Sites were burned, after which we compared methods for characterizing fire, particularly the ability of pyrometers and calorimeters to predict values derived from thermocouples.Results: Pyrometers best predicted peak 1-minute mean temperatures and were least successful at estimating maximums. Calorimeters were associated with the number of minutes maximum temperatures exceeded 60 °C, but were damaged at high residence times and inconsistent at low temperatures. Both pyrometers and calorimeters detected site and treatment differences in fire intensities. These analyses and logistic considerations give pyrometers an edge over calorimeters in situations where dataloggers are impractical. Mechanical pre-treatments to fire altered fire parameters. Mowing reduced fire temperatures but had different effects on areas burned; this was related to the length of time elapsed between mowing and burning. Subcanopy felling increased both fire coverage and temperatures.Conclusion: Pyrometers outperformed calorimeters as a cheap method for describing relative temperature regimes that are a function of both temperature and residence time. Pyrometers were able to demonstrate how mechanical treatments applied prior to prescribed burning altered fire parameters. Pyrometers are a useful tool for investigating biological responses to fire at multiple scales and in heterogeneous vegetation.Abbreviations: AREA60 = the integrated area under the instantaneous temperature curve defined by a threshold of 60 °C; AREA150 = the integrated area under the instantaneous temperature curve defined by a threshold of 150 °C; CALOR = mean percent water loss from calorimeters adjusted for evaporation; MAX = peak instantaneous temperature (°C); MAX60 = number of minutes where the instantaneous temperature > 60 °C; MAX150 = number of minutes where the one minute mean temperature > 150 °C; MEAN = peak one minute mean temperature (°C); MEAN60 = number of minutes where the one minute mean temperature > 60 °C; MEAN150 = number of minutes where the one minute mean temperature > 150 °C; PYRO = median pyrometer reading.Nomenclature: Wunderlin & Hansen (2003).

Effect of fire on ground beetles and ant assemblages along an environmental gradient in NW Patagonia: Does habitat type matter?

xx7:The response of beetle and ant assemblages to fire (2–5 y old) and the dependence of that response on habitat type were analyzed. Using pitfall traps, beetles (Coleoptera) and ants (Formicidae) were sampled in replicated forest, scrub, and steppe areas including paired unburnt and burnt plots. A total of 176 species of beetles (8245 individuals) and 22 species of ants (115,056 individuals) were captured. Most beetle families (65%) were captured in the forest, while most ant species were most frequently captured in the steppe (45%). Beetle abundance was the same in unburnt and burnt plots in the three habitats, but ant abundance was higher in burnt than in unburnt plots. Fire usually decreased species richness of both taxa, but the strength of this effect depended on the habitat type. Coleoptera richness was lower in burnt than in unburnt plots in the forest and steppe but was the same in unburnt and burnt scrub plots. Ant richness was lower in burnt forest and scrub plots and was similar between burnt and unburnt steppe plots. For both taxa, species composition of the forest assemblages was different between unburnt and burnt forest plots (difference almost significant for ants) but not between unburnt and burnt steppe plots. Beetle species composition in the scrub was different between unburnt and burnt plots, but ant species composition was the same. Our results support the idea that the consequences of fire on native beetle and ant assemblages depend on the habitat type but also on the taxonomic group under analysis. Beetles and ants showed differences in their habitat preference and in the way that they use the habitats (e.g., preference for vegetated or bare soil patches) along the environmental gradient. These differences explain why beetles were in general more severely affected than ants, and why fire differentially affected both taxa in the scrub (habitat of intermediate complexity). A good knowledge of the habitat utilization by different groups at the local scale and a regional perspective (e.g., habitat preference along an environmental gradient) are necessary to fully understand the effect of disturbances on native arthropod assemblages.

Spatial and temporal distributions of two sympatric Homalodisca spp. (Hemiptera: Cicadellidae): Implications for areawide pest management

Four-year landscape-scale monitoring was conducted to investigate dynamics of the spatial and temporal distributions of Homalodisca coagulata and H. liturata and their spatial associations with the surrounding vegetation. Temporal trap catches of H. liturata and H. coagulata showed two peaks per year, and the peaks of the two species coincided. Spatial analysis with distance indices (SADIE) showed that spatial distributions of each species were significantly consistent between years. All patches (i.e. clusters of significantly high trap catches) of H. coagulata were located near citrus, and no patch was found in urban landscapes. Major patches of H. liturata and major gaps (i.e. clusters of significantly lower trap catches) of H. coagulata were located in desert saltbush scrub and urban areas, resulting in negative spatial association between the two species. Between-year spatial consistency of H. coagulata and H. liturata and their spatial relationship with the surrounding vegetation implies that areawide management targeting specific areas would be possible by identifying the patches and gaps of H. coagulata and H. liturata in space and time.

Behavioural aspects in ass during the end of pregnancy and ass and their foal during the first week post–partum in Martina Franca breed

The study was carried out to investigate behavioural pattern in ass during the end of pregnancy and in asses and their foals during the first week after foaling. The study was performed on a total of 17 asses and 8 foals of Martina Franca breed reared outdoors free- ranging over the natural scrub area. In particular, for the behavioural observations on ass before the foaling 9 asses on the last month of pregnancy were considered, while, during the first post-partum week the observations were performed on 8 couples of dams and their foals. The behavioural observations were performed in a fenced area (4000 m2) from 08:00 to 20:00 using scan sampling with 5 min intervals. The data were collected by trained observers and recorded on a protocol form which considered the following main behavioural aspects: eating, drinking, walking, resting up, standing, and other behaviours. Within the class of other behaviours it was included secondary behaviours as grooming, vocalisation, playing, defecation, sniffing. For the foals the other behaviours included also suckling, interactions with their dams or other foals. The results show that the status of end of pregnancy or post-partum had a low impact on the main behaviours of ass. Percentage of time for eating in ass was higher (P<0.01) during the p.m. hours respect to the a.m. hours. During the first week, foals spend a higher (P<0.01) time for suckling during a.m. hours versus p.m. hours of the day. The suckling frequency was higher in a.m. (32 min vs. 41 min of p.m. hours). The results of this study represents preliminary data of etogram of ass and foal reared in semi-extensive conditions.

Habitat availability and use by Turtle Doves Streptopelia turtur between 1965 and 1995: an analysis of Common Birds Census data

Capsule Breeding density on long-term CBC plots fell in proportion to loss of nesting rather than feeding habitat. Aim To investigate the habitat requirements of Turtle Dove and relate changes in breeding density to changes in habitat, at the national scale. Methods Bird and habitat data were extracted from 30 long-term farmland and woodland CBC plots for the period 1965 to 1995. Results Turtle Dove densities declined at an average annual rate of 4.6% on both farmland and woodland plots, equal to a decline of 76% over the period 1965 to 1995. Turtle Dove density on the woodland plots was, on average, 6.5 times greater than on the farmland plots. Overall habitat availability did not change over time, but some finer measures of habitat quality, such as habitat diversity, nesting and feeding habitat availability did change. Changes in Turtle Dove density were positively related to changes in the amount of hedgerow and woodland edge per unit area on the farmland CBC plots, where Turtle Dove territories contained three times more woodland than expected from availability. On the woodland CBC plots, territories were established apparently at random. Conclusion It is likely that the availability of nesting habitat dictates Turtle Dove density, with areas of woodland and scrub supporting on average 6.5-times more breeding Turtle Doves, per unit area, than farmland.

Spatial and temporal patterns of phlebotomine sand flies (Diptera: Psychodidae) in a cutaneous leishmaniasis focus in northern Argentina.

Phlebotomine sand flies (Diptera: Psychodidae) were captured in an area of Argentina endemic for American cutaneous leishmaniasis (ACL). A total of 44,944 flies were collected during a 130-wk interepidemic period from 1990 through 1993. These sand flies included Lutzomyia neivai (Pinto) (97.8%), Lutzomyia migonei (Franca) (1.2%), Lutzomyia cortelezzii (Brèthes) (0.8%), Lutzomyia shannoni (Dyar) (0.1%), and Lutzomyia punctigeniculata (Floch and Abonnenc) (0.1%). Lutzomyia neivai was more abundant in secondary forests and peridomestic environments associated with human cases than in primary forest or xeric thorn scrub areas. Time series analyses of species densities suggested a bimodal or trimodal annual pattern related to rainfall peaks, a 5-wk reproductive cycle, and peridomestic local populations that were located adjacent to secondary forests. In general, sand fly abundance was correlated with the rainfall of the previous year. Lutzomyia neivai spatial distributions were consistent with ACL incidence patterns during the study and in the recent outbreaks in Argentina. However, Lu. migonei also may be involved in peridomestic transmission. Our results suggest that there is a need for improved, long-term surveillance of sand flies and ACL cases, as well as development of effective intervention strategies.

Biogeographical zonation of African hornbills and their biotic and geographic characterisations

We studied the geographic ranges of the 23 African hornbill species using countries as distribution units, to search for either groups of similar distributions (chorotypes) or gradual replacement of species as two different types of distribution patterns. We used a probabilistic classification method to distinguish between these two types of biogeographic patterns. Then we analysed the influence of climate, area, surface covered by different types of habitat, and human disturbance in each country, as well as biotic features of the species involving the habitat preference, feeding requirements and habits, body size, sexual dimorphism, and metabolic parameters, on the biogeographic patterns detected. We found that 20 species were significantly classified into three chorotypes. The western-central chorotype comprises nine species characterised by their preference for forest habitat and their low sexual body mass dimorphism. These species occur in 25 countries, characterised by their low range of temperatures. The eastern chorotype includes three species characterised by their preference for feeding on the ground and greater dimorphism in mass between the sexes. Seven countries, characterised by their high values of savanna and grassland surface area, constitute the geographic element of this chorotype. The southern chorotype involves the distribution of eight species characterised by their preference for montane and coastal forests or woodlands. Eighteen countries fall into this chorotype and are characterised by their low values of temperature in the coldest month and greater surface area of desert scrub and desert forest. The other three species replace each other mainly following a gradual pattern within the study area.

Lizard Community Response to a Desert Shrubland-Intertidal Transition Zone on the Coast of Sonora, Mexico

The Sonoran coast of Mexico is characterized by an abrupt transition from marine bay to inland desert. We surveyed lizard species along 141 transects in desert shrubland, desert-dune scrub transitional, dune scrub, and sandy intertidal habitat areas within this transition zone. Cnemidophorus tigris, Uta stansburiana, and Callisaurus draconoides accounted for > 99% (N = 353) of individuals identified. Cnemidophorus tigris was almost entirely restricted to desert shrubland, U. stansburiana was mostly restricted to desert shrubland and desert-dune scrub transitional habitats, and C. draconoides was the most generalized in habitat use. It exhibited strong preferences for bare ground and was the only species observed in the sandy intertidal zone, an area devoid of vegetation. The intertidal zone had the highest lizard biomass of the four habitats but was completely dominated by a single species. Total lizard density and biomass were substantially less in desert shrubland, but lizard diversity was greatest in this structurally complex habitat. We suggest that habitat structure regulates lizard diversity, whereas food resources control lizard density across the transition zone.

Application of GIS and remote sensing for measuring and evaluating land-use change and its impact on water quality in the Pinang River watershed

Human activities in the Pinang River watershed have dramatically changed landuse and land cover characteristics, and have subsequently altered hydrological and watershed processes. Pinang River water quality in downstream areas is badly polluted, based on the Malaysian Department of Environment-Water quality index (DOE-WQI) classification. In order to assess the past and present water quality and the possible uses of the Pinang River, a water quality index was applied to a data set collected for this study, which is based on the Malaysia DOE-WQI standards. This study investigated the land-use and land cover changes, which are the main contributors to the water quality and hydrological problems in this watershed. With some information derived from Landsat images, Geographic Information System (GIS) application and land-use/land cover map, we identified the land-use changes and landscape patterns in the Pinang River watershed. The results showed that forested and scrub areas decreased rapidly within the sub-watersheds as well as the entire watershed, in contrast to the urban or built-up areas. Statistical analysis indicates that impervious land parcels are increasing, which contribute to water pollution and watershed degradation. Based on land-use fragmentation and diversity indices, it was revealed that these indices are reliable tools for measuring and evaluating land-use and land cover changes for the general guideline for watershed management. This study revealed that integration of GIS and remote sensing (RS) data to quantify landscape structure is a feasible and efficient method for evaluating the temporal effect of land-use activities in the river basin for watershed planning and future development.

Fragmentation of Florida scrub in an urban landscape

The Florida scrub community is considered a biodiversity hotspot due to the high degree of endemism and the number of species restricted to a few counties or fragments. Florida scrub habitat is officially listed as an imperiled ecoregion of global importance because it is a geographically restricted habitat with a high diversity of rare and endemic flora. This study examines landscape metrics and plant species richness of scrub in Pinellas County, which is the most densely populated county in Florida and once contained large areas of Florida scrub. Landscape metrics on scrub area, historic xeric upland area, naturally vegetated upland area within proximity, isolation indices, disturbance, and soils were collected for the 20 largest and best remaining fragments of scrub in Pinellas County from Geographic Information Systems map layers, Digital Ortho Quarter Quadrangles, and field validation. Landscape metrics were compared with three categories of species richness: scrub species richness, obligate scrub species richness, and richness of species listed as threatened or endangered. All categories of species richness in remaining Florida scrub fragments in Pinellas County were significantly associated with area of remaining scrub habitat. Site elevation was associated with obligate scrub species richness and degree of disturbance was associated with higher species richness for listed species. We conclude that large areas of scrub in higher elevated uplands and active management in the form of prescription burning will be needed to ensure the persistence of a number of endemic scrub specific species within remaining fragments.

Phylogeny of the Macaronesian endemic Crambe section Dendrocrambe (Brassicaceae) based on internal transcribed spacer sequences of nuclear ribosomal DNA

The 14 species of Crambe L. sect. Dendrocrambe DC. (Brassicaceae) form a monophyletic group endemic to the Canary and Madeira archipelagos. Both parsimony and maximum likelihood analyses of sequence data from the two internal transcribed spacer regions of nuclear ribosomal DNA were used to estimate phylogenetic relationships within this section. These analyses support the monophyly of three major clades. No clade is restricted to a single island, and therefore it appears that inter-island colonization has been the main avenue for speciation in these two archipelagos. The two species endemic to Fuerteventura (C. sventenii) and Madeira (C. fruticosa) comprise a clade, providing the first evidence for a floristic link between the Eastern Canary Islands and the archipelago of Madeira. Both maximum likelihood and weighted parsimony analyses show that this clade is sister to the two other clades, although bootstrap support for this relationship is weak. Parsimony optimizations of ecological zones and island distribution suggest a colonization route from the low-altitude areas of the lowland scrub toward the high-elevation areas of the laurel and pine forests. In addition, Tenerife is likely the ancestral island for species endemic to the five westernmost islands of Gran Canaria, La Gomera, El Hierro, La Palma, and Tenerife.

Late Glacial beech forest: an 18,000–5000-BP pollen record from Auckland, New Zealand

Australia, New Zealand and South America are the main sources of terrestrial climate change records for midlatitudes in the Southern Hemisphere. The advantage of studying the New Zealand record is that its vegetation has been subject to human influence for only the last thousand years. Vegetation records for Auckland are important because earlier work indicates that during the Last Glacial Maximum, the boundary between scrubland and forest lay in the Auckland region. Auckland is situated in a volcanic field and the coring site was in the crater of a small extinct volcano (Crater Hill, formed about 29 ka BP). The 4-m long core contained sediment dating from c. 5 to c. 18 ka BP. We present pollen and diatom records from this core. The pollen records from basal clays indicate southern beech forest (mainly Nothofagus menziesii) was present in the region around Crater Hill from 18 to 14.5 ka BP. At this time, there were areas of scrub in the crater surrounding a hardwater lake. The southern forest limit could well have been close to the site. Records from overlying peat indicate beech forest was replaced by Podocarp broadleaf forest as the Last Glacial ended. Metrosideros spp. (coastal forest trees) peak in the early Holocene. This coincides with an impoverished diatom flora which indicates drier conditions in the basin. When the lake reformed in the Holocene on peat its water was more acidic.

Hydroclimatic Conditions in Subtropical Dry Scrub on Chichi-jima Island the Ogasawara (Bonin) Islands

Although the climatic environment has not been quantified, it is commonly believed that subtropical dry scrub is distributed in the dryer areas of Chichijima Island in the Ogasawara (Bonin) Islands, the northwestern Pacific. To clarify the hydroclimatic conditions of subtropical dry scrub, year-round atmospheric and soil moisture observations were carried out in an area of subtropical dry scrub at Hatsune-yama Point in the eastern part of Chichijima Island. In the summer of 2001, the forest height and cover ratios of all scrub and forest species, and soil moisture, were measured at twelve sites on the island, including Hatsuneyama Point, along an east-west transect across the ecotone between subtropical dry scrub and secondary mesic forest. The subtropical dry scrub was not distinguished from the mesic forests by year-round dry atmospheric conditions; annual precipitation was larger and potential evaporation weaker at Hatsune-yama Point than at Chichijima Observatory on the western side of the island. At the former, however, the lack of precipitation and the very high potential evaporation extremely depleted soil moisture, to less than 20 volumetric %, during the summer, just after the rainy season. This severe depletion of soil moisture occurred only in the areas of subtropical dry scrub, and, consequently, formed a dry-wet gradient of soil moisture across the ecotone between the subtropical dry scrub and the secondary mesic forest. Since forest height was significantly correlated with this dry-wet gradient of soil moisture, the degree of depletion of soil moisture during summer just after the rainy season presumably affects forest structure on Chichijima Island. Based on these results, we conclude that subtropical dry scrub is distributed only in areas with seasonally dry edaphic conditions. This demonstration of hydroclimatic conditions using observational data implies that edaphic heterogeneity determines the vegetation pattern on Chichijima Island.

Fragmented native woodlands in Snowdonia (UK): assessment and amelioration

The purpose of this work was to study the landscape characteristics of the forests and woodlands in the Snowdonia National Park, North Wales (UK). Using a geographical information system, several landscape indices were calculated for the broadleaves, conifers, mixed high forest and scrub vegetation categories. A total of 3967 woodland fragments, covering an area of 216 664 ha, were analysed in terms of their area, density, degree of isolation and shape in order to understand their spatial distribution and connectivity. The analyses showed that the broadleaved habitat is dissected into a great number of patches, irregular in shape and with a mean patch size of <4 ha. Fragments of mixed forest had similar sizes and were more isolated across the landscape. Scrub contained many small and similar‐sized patches, more regular in shape. When these habitats were analysed using an edge width of 100 m,∼99 per cent of the total scrub area was found to lie within edge habitat. Conifer forest presented as a very clumped habitat containing larger patches with higher variability in size. Objective GIS simulation techniques for ameliorating this fragmentation of the broadleaves, mixed forest and scrub were demonstrated using two sites in the Park. Simulations using these techniques show that (1) conversion of conifers to broadleaves, (2) reforestation of agricultural land between woodland fragments or (3) creating buffer zones around existing woodland would considerably increase the area of interior or core habitat and connectivity between the presently fragmented native woodland.

Decline of roller dung beetle (Scarabaeinae) populations in the Iberian peninsula during the 20th century

A historical compilation of data on roller dung beetle occurrence in the Iberian peninsula was examined for temporal changes between the first and second half of the 20th century. Analysis of changes in the relative frequency of database records, individuals and 10-km UTM cells where the beetles occurred showed a decline in the occurrence of nine of the eleven species. A comparison of latitudinal and longitudinal mid-points of the 10-km UTM cells where each species occurs indicated that the range of most roller dung beetles in the Iberian peninsula has also contracted. Before 1950 a significant, positive and curvilinear relationship was found between the number of roller dung beetles and the area of coastal environments (sea, dunes, beaches and marshes); while in the second half of the 20th century the number of “roller” species is positively correlated with artificial pastureland and scrub areas. It is suggested that urban development of the coastal zones for tourism since 1950 has probably contributed greatly to the disappearance of many roller populations. It is recommended that some of the more affected species of roller dung beetles should be considered for inclusion among protected invertebrates.