British Habitats Research Articles

A Celebration of British Habitats and a Personal Perspective on Its Birds of Prey

A Celebration of British Habitats and a Personal Perspective on Its Birds of Prey

Influence of Holocene environmental change and anthropogenic impact on the diversity and distribution of roe deer

Extant patterns of population structure and levels of diversity are a consequence of factors that vary in both space and time. Our objective in this study is to investigate a species that has responded to both natural and anthropogenic changes in ways that have shaped modern populations and provide insight into the key processes. The roe deer (Capreolus capreolus) is one of the two species of deer native to Britain. During the last glacial maximum (LGM), the British habitat was largely under ice and there was a land bridge to mainland Europe. As the Earth warmed during the early Holocene, the land bridge was lost. Subsequent hunting on the British mainland left the southern region extirpated of roe deer, whereas a refugial population remained in the north. Later reintroductions from Europe led to population expansion, especially in southern United Kingdom. Here, we combine data from ancient and modern DNA to track population dynamics and patterns of connectivity, and test hypotheses about the influence of natural and anthropogenic environmental change. We find that past expansion and divergence events coincided with a warming environment and the subsequent closure of the land bridge between Europe and the United Kingdom. We also find turnover in British roe deer haplotypes between the late-Holocene and modern day that have likely resulted from recent human disturbance activities such as habitat perturbation, overhunting and restocking.

Nitrogen deposition causes widespread loss of species richness in British habitats

AbstractWe use national scale data to test the hypothesis that nitrogen (N) deposition is strongly negatively correlated with plant species richness in a wide range of ecosystem types. Vegetation plots from a national ecological surveillance programme were drawn from heathland, acid, calcareous and mesotrophic grassland habitats. Mean species number and mean plant traits were calculated for each plot and related to atmospheric N deposition. There was a significant reduction in species richness with N deposition in acid grassland and heathland even after fitting covarying factors. In acid grassland and heathland, evidence from trait changes suggested that acidification rather than increased fertility was responsible for species loss. In contrast, calcareous grassland showed evidence of eutrophication in response to increasing N deposition. Loss of species richness from chronic N deposition is apparent in infertile grasslands and heathland. Mechanisms associated with loss of species richness differ between habitats so mitigation of N deposition should be targeted to habitat type.

The dimensions of land use change in rural landscapes: Lessons learnt from the GB Countryside Surveys

Rural landscapes are highly dynamic and their change impacts on a number of ecological processes such as the dynamics of biodiversity. Although a substantial amount of research has focused on quantifying these changes and their impact on biodiversity, most studies have focused on single dimensions of land use change. This lack of integration in land use change studies can be explained by the fact that data on the spatial, temporal, and ecological dimensions of land use are seldom available for the same geographical location. In this paper, the benefits of taking into account these three dimensions are illustrated with results derived from the Great Britain Countryside Surveys (CS), a large-scale monitoring programme designed to assess change in the extent and ecological condition of British habitats. The overview of CS results presented in this paper shows that (1) changes in land use composition will translate into a variety of spatial patterns; (2) the temporal stability of land use is often lower than can be expected; and (3) there can be large-scale shifts in the ecological condition of the land use types that form our rural landscapes. The benefits of integrated rural landscape studies are discussed in the context of other national monitoring programmes.

Holocene climate changes and warm man‐made refugia may explain why a sixth of British butterflies possess unnatural early‐successional habitats

Analyses of their habitats indicate that 18% of British butterfly species are restricted to the earliest seral stages of ecosystems, whereas the same species occupy later seral stages in central Europe, where spring and summer temperatures are warmer. The microclimates of their British habitats are exceptionally warm, compensating for the cooler climate. Most of these British habitats are also ephemeral, and have long depended on man for their creation and regeneration This poses the question of where these species lived before man created their habitats, roughly 6000 BP, I suggest that they are relics from a period when British summers were warmer than today, and that they avoided extinction when the climate cooled by moving into warm refugia created by prehistoric man within three types of ecosystem If summer temperatures become warmer, these species should return to later seral stages that are commoner and less dependent on man.

STUDIES ON FRESHWATERAMPHORASPECIES. III.AMPHORA PEDICULUS(KÜTZ.) GRUN. AND SOME POSSIBLY RELATED FORMS

Amphora pediculus (Kutz.) Grun. has been investigated in some detail in order to compare the species from British habitats with those from elsewhere. In addition, several forms have been recognised, some of which may ultimately require recognition as species.

Management history in relation to changes in the flora of different habitats on an Oxfordshire Estate, England

Comprehensive species lists of the vascular flora of ht eWytham estate near Oxford have been made at several times between 1880 and 1985. These lists were used to assess the effects of particular changes in management on the flora. The data were also used to estimate maximal values for natural (with no change in management) species turnover in different habitats. Natural turnover, except among arable weeds, was very small compared to the rates of change arising from new management practices. The development of modern farming and forestry caused many extinctions. Declines of traditional woodland use, such as coppicing, and in rabbit grazing had less effect, but nevertheless gave rise to some extinctions. When appropriate management was resumed, many plants reappeared which had been considered extinct; new ones also appeared. Even the cutting of scrub on limestone grasslands (cheap and easy compared to artificial grazing) prevented extinctions there. The results suggest that, at least in British habitats with a long history of human use, management considerations are much more important than island biogeography phenomena are to the choice and design of nature reserves.

Estimating numbers of birds by point counts: how long should counts last?

In the British habitats studied, most species and pairs were seen within 10 minutes. Hence longer point counts are a poor investment of time.

Observations on the growth and production of chub Leuciscus cephalus and dace Leuciscus leuciscus in a small lowland river in southeast England

SUMMARY. The River Eden (Kent, England) holds a mixed coarse fish population in which minnows (Phoxinus phoxinus), gudgeon (Gobio gobio), chub (Leuciscus cephalus) and dace (Leuciscus leuciscus) are numerically predominant. Chub and dace provide the major interest to anglers and their growth and production were studied. Observed growth rates of both species were marginally below recorded averages from other British habitats. Back‐calculations showed that year‐class strength and relative growth rates varied between years. Instantaneous mortality rate Z was 0.147 for chub aged 1–10, 0.438 for chub aged 10 and over, and 0.172 for dace. Exclusive of the 0‐group, fish numbers, biomass (wet wt) and production were found to be 0.1305 m‐2, 19.12 gm‐2 and 5.38 gm‐2 year‐1, respectively, for chub and 0.0968 m‐2, 4.33 gm‐2 and 1.69 gm‐2 year‐1 for dace. Smoothing of data produced theoretical production figures of 6.69 gm‐2 year‐1 for chub and 1.15 gm‐2 year‐1 for dace.

Anthoceros agrestis, a new name forA. punctatusvar. cavernosus sensuProsk. 1958,non(Nees) Gottscheet al.

Anthoceros punctatus var. cavernosus Prosk. homon. illeg. is renamed A. agrestis Paton, redescribed, illustrated and compared with A. punctatus L. (A. husnotii Steph.). The thalli and sporophytes are usually smaller in A. agrestis than in A. punctatus and the antheridial bodies are significantly smaller. World distributions and brief descriptions of British habitats are included for both species showing that A. agrestis is more restricted than A. punctatus in its distribution and ecology.

GENECOLOGICAL STUDIES OF LEAD TOLERANCE IN GROUNDSEL (SENECIO VULGARIS L.)

SUMMARYSoils from a range of native British habitats for Senecio vulgaris L. have been found to contain significantly different amounts of lead ranging from several hundred parts per million along roadsides and on rubbish dumps to minute quantities in coastal sandy soils. Root growth of seedlings in simple water culture revealed different degrees of tolerance between topodemes to soluble lead, apparently related to the lead content of the soil. Studies of root growth in a range of native soils suggest a more complex relationship between growth and lead content. The genecological implications of these findings are discussed, including the possibility that lead‐tolerant roadside variants may be of recent origin.

Vulpia sicula and the Genus Vulpia

Vulpia sicula Link, a rare perennial grass of the western Mediterranean region, is of vital significance in studies of the evolution and taxonomy of the genus Vulpia. The most recent herbarium specimens we have found either in Britain or abroad date from the 1880s and a field expedition to areas where the plant is native was made to obtain living plants or viable seed. In May/June 1972 we visited various parts of Sicily (the centre of its distribution) and located the plant in great abundance in the Bosco della Ficuzza at about 800 m on the northern slopes of Rocca Busambra, 30 km south of Palermo and sparsely on the lower slopes of La Pizzuta at about 750 m just west of Piana degli Albanesi, 15 km south of Palermo. It grows in permanent, rich, closed pastures in a habitat quite unlike that of any other Vulpia. Although other species of Vulpia (V. bromoides (L.) Gray, V. myuros (L.) C.C.Gmel., V. broteri Boiss. & Reut., V. ciliata Link and V. ligustica Link) occur in the vicinity they all occupy open or disturbed areas similar to their British habitats. We were unsuccessful in our searches for V. sicula in its recorded localities in the hills of Le Madonie, 60 km south-east of Palermo. All of the seven plants we collected have grown vigorously and flowered in a cool glasshouse at Manchester.

Cuckoo Hosts in British Habitats

Cuckoo Hosts in British Habitats