Durham E-Theses Ecological studies on moorland ground beetles (coleopteran : carabidae) Houston, W. W. K. How to cite: Houston, W. W. K. (1970) Ecological studies on moorland ground beetles (coleopteran : carabidae), Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/8766/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk ECOLOGICAL STUDIES ON MOORLAND GROUND BEETLES (COLEOPTERA : CARABIDAE) by W.W.K. Houston, B.Sc. (St. Cuthbert's Society) ••»•••••••••• being a thesis presented in candidature for the degree of Doctor of Philosophy in the University of Durham, 1970. ACKNOWLEDGMENTS The writer wishes to express his sincere thanks to Dr. J.C. Coulson for his help and criticism throughout the study, and to Professor D. Barker for providing facilities in the Department of Zoology, Durham. I would also like to thank : Members of the Department of Zoology for helpful discussion and advice, The staff of Moor House Research Station, and Tom Buffey, the Site Research Officer at Cow Green, for their generous assistance and hospitality, Dr. M.L. Luff for the identification of some of the material, particularly the larvae, ~Dr. J.W~Coles of the British Museum (Natural History) for identifying the Nematomorpha, Mr. E. Henderson for photographic assistance, Mrs. Ruth L. Reed for typing the final draft, and Aileen, for many reasons. The work at Cow Green was supported by a grant from the I.C.I.. Teesdale Trust Fund. CONTENTS I. INTRODUCTION 1 II. STUDY AREAS AND SAMPLING SITES 3 1. Location and physiography . ... 3 a) The Moor House National. Nature Reserve 3 b) Cow Green *f 2. Climate ««• ••« •*• ... ... a) Moor House ... *f b) Cow Green ... ... ... ... ••• 6 3. Sampling sites 6 a) Moor House : Sites 1-6 ... ... 6 b) Cow Green r Sites 7-9 10 III. SAMPLING METHODS. 12 1. Pitfall trapping 12 a) Method ... ... ... ... ... 12 b) Pitfall trap sites and trapping details 16 I. Moor House ... ... _l6 II. Cow Green 18 III. Miscellaneous Sites 18 2. Hand collecting 19 3* Soil samples ... ... ... ... ... 19 k. Soil sieving 20 3. S/tomach analysis of predators 20 IV. EXAMINATION OF SPECIMENS 22 1. Adults ... ... ... ... 22 A. Species .*• . •. •*• ... 22 B. Condition of mandibles and claws ... 23 C. Wing length 23 D. Reproductive condition 23 i. Females .. ... ... •• ••• 24 a) Teneral 24 b) Immature but not teneral ... 25 c). Developing . 25 d) Mature . ... 25 e) Spent ... ... ... ••• 26 ii. Reproductive state of the males .. 2? a) Teneral 27 b) Immature but not teneral ... 27 c) Developing .. 28 d) Mature 28 E. Fat reserves ... 28 2 •• Larvae ... ••• ... ... ... 29 3 • Pupae ... ... ... ... 29 V. THE SPECIES. -RESULTS 30 1.. Distribution and abundance 30 2. Altitude and fauna size 33 3. Colour polymorphism 35 a) Nebria rufescens .. 35 b) Pterostichus madidus ... 38 c ). "Calathus melanocepKarus- " ~ 40 d) Agonum ericeti ... 40 4. Life history patterns . ... ... 43L a) Introduction ... ... 4-1 bj Life history patterns at Moor House and Cow Green . ... 42. i. Viet species ..... ... ... 46 ii. Non-wet species 47 iii. Miscellaneous life history patterns 48 c) Life history patterns and habitat distribution of Patrobus assimilis. and P.atrorufus ... .. 56 5. Wing condition ." 58 6. Wing condition and habitat 63 7. Diurnal activity 65 a) Introduction 65 b) Direct observation 66 c) Pitfall trapping ... ... 67 i. Manual 67 ii. Mechanical 69 d.) Frog stomach analysis 72 8. Daily activity times at. Moor House, and Cow Green ... ... 72 9.. Mandible condition 77 a) Introduction ... 77 b) Carabus glabratus .. 78 c) Carabus problematicus ... 80 d) Mark-release experiments . 8l 10. Resistance to desiccation and drowning ... 8l a)! Introduction ... 8l b) Resistance to dSoiro&xg*^, ... ... 82 c) Resistance to desiccation 86 11. Predators and. parasites 87 a) Introduction... ... .. ... ... 8? b) Invertebrate predators .. 87 c) Vertebrate predators 88 i. Frogs .. ... ... ... ... 88 ii. Shrews . ... ... ... ... 90 iii*. Birds .. ... ... ... ... 91 iv. Sheep .. ... ... ... ... 91 d) Parasites 91 i. Hymenoptera ... 91 ii. Nematomorpha 92 VI. LABORATORY CULTURES .. ... Sk 1.. Method 9^ a) Containers ... .... ... ... 9^ b) Humidity 9^ c) Food ... ••• ••• ••• 95 d) Temperature .. ... 96 e) Acclimatisation .... ..r 97 f) Photoperiod 97 2. Experiments ... ... ... •> ... 98 a-c Gonad development in : a) immature Patrobus assimilis ...., 98 b) mature Patrobus assimilis ... .100 c) overwintering Patrobus assimilis ... 106 d) Fat production in Patrobus assimilis 109 e:) Patrobus assimilis;egg development ... Ill f) P.assimilis : larval development ... 113 g-m Gonad development in : g) Pterostichus nigrita females ... 117 h) mature P.nigrita adults- ... 118 i). overwintering P.nigrita adults; ... 120 j); Carabus problematicus. females 122 k)-: Pterostichus ad's trie tus adults: .. ... 12 k 1) "E.s.trenuus adults ... ... ... ... 12*f ml Loricera pilicornis adults 125 3. Summary of main results of culture experiments 126 VII. GENERAL DISCUSSION SUMMARY REFERENCES APPENDIX I. Notes on individual species- (in alphabetical order) AT. II. A', guide to the British sjscies of the genus Patrobus £31 III.. Taxonomic observations on Nebria larvae A39 IV. A mechanical time sorting pitfall trap A&2 V. A, reliable and permanent method of marking Carabidae A'^5 I. INTRODUCTION Pearsall (1950) remarked that "Upland Britain ..... is equal in area to lowland Britain". Despite this large expanse, which is mainly mountain and moorland (Hart 1955), the Carabidae of these areas have received little attention. Sharp (1916) mentions some common beetles to be found in upland areas, and more recently Davidson (1961) published some notes on Cumberland and Westmorland Coleoptera, which included some Carabidae records from the north Pennines; Pearson & White (1964) listed some Carabidae from moorland in north Wales; Greens lade (1968) discussed some Carabidae found in Argyll, Scotland, and Goodier (1968) some Coleoptera found on Welsh mountains. Cragg (1961) discussed some aspects of the ecology of moorland animals and stressed the need to evaluate the functions of organisms in the ecosystem. But many studies on the moorland- fauna have been concerned mainly with distribution and numerical abundance of a few common species or groups and knowledge of their role in the ecosystem is often only superficial. With the initiation of the International Biological Programme on tundra and sub-arctic terrestrial ecosystems (in 1967), the emphasis in the moorland ecosystem is now on biomass and energy turnover, but progress in this field is often being restricted by the lack of basic biological information on many of the organisms. 2 By studying a limited range of organisms on moorlands, several workers emphasise the patchy distribution of individual species and the habitat mosaic filled with different species (Block 1963; Cherrett 1961; Hadley 1966). They have also stated that predators and parasitism appear to have negligible effect on the numbers of dominant insects, and have demonstrated how single environmental factors dominate changes in density, and may be used to predict future densities. As the determination of the densities of most Carabid species is often a highly erratic and disruptive process and of little value unless related to other factors, the emphasis in this study is on quality and not the quantity of the Carabid fauna. It attempts to evaluate the status of the Carabidae on moorland fairly typical of the north Pennines, with emphasis on habitat and life history phenomena, and to lay a broad foundation for any future detailed investigation. 3 II. THE STUDY AREA AND SAMPLING SITES 1. Location and physiography Most of the work described in this thesis was conducted on the Moor House National Nature Reserve (N.R.80 : Nat.Grid,Ref. NY/758329) (Conway 1955). A subsidiary study was conducted on the Cow Green area of Widdybank Fell, Upper Teesdale (Nat.Grid. Ref. NY/812301) (Bellamy et al 1969). a) The Moor House Reserve The Moor House Reserve (Fig.l) occupies 10,000 acres (4,000 hectares) of moorland typical of the northern Pennines. Situated in Westmorland, 12 miles to the east of Penrith and 11 miles to the south of Alston, it is separated from County Durham by the River Tees (which forms part of its northern and eastern boundary) and is less than 4 miles from the Yorkshire border. It features the characteristic dip and scarp slopes of the northern- Pennines. The three principal fells, Knock Fell (2,604ft; 794m), Little Dun Fell (2,761ft; 842m), and Great Dun Fell (2,780ft; 845m), form the summit ridge which is continuous with Cross Fell (2,930ft; 893m), the highest peak of the Pennines, lying just outside and to the north of the reserve. The entire area is dissected by numerous streams which flow into the River Eden on the west, and the River Tees on the east. Only the main streams are shown in Fig.l. FIGURE 1 Map of the Moor House National Nature Reserve, showing the location of the major pitfall trap sites (black rectangles 1-6) and the main miscellaneous pitfall sites (black circles) 1 V 1 > N ri V ( A V \ ui O 2 " in Ui Ui \ OO \ \ ) Ui u Oo HQ (/) _j o O ui m 4 The bed rock consists chiefly of the Carboniferous Yoredale series, a complex series of beds of limestone, sandstone, shale and coal, covered extensively by glacial drift overlaid by peat.