Faculty of Biological Sciences

Dr Steven Sait

BSc, Nottingham; PhD 1991, Liverpool.
Reader in Ecology
School of Biology

Background: My research career began at the University of Liverpool where I completed my PhD and first postdoctoral position. I then had a spell at the NERC Centre for Ecology and Hydrology in Oxford before returning to Liverpool with a 5-year NERC Advanced Fellowship. I moved to Leeds in 2002 with a 5-year Leeds University Research Fellowship.

Contact:  Manton 8.08 | +44(0) 113 34 37039 | email address for  

Research Interests

Population, community and evolutionary ecology

Predator-prey
interaction

I am interested in insect population and community ecology and evolution, with an emphasis on natural enemies (predators, parasitoid wasps and parasites). Major themes focus on mechanisms underlying patterns in abundance, species co-existence and community structure, predator-prey interactions and the co-evolution of host resistance and parasite virulence. I use simple laboratory systems as biological analogues of the real world. Coupled with mathematical modelling, this approach represents a powerful tool for dissecting the mechanisms underpinning interactions within and between species. Using various combinations of species in the lab., we construct simple communities and explore a wide range of contemporary questions. Can a natural enemy enable competing prey species to co-exist? What happens when two natural enemies compete for the same prey? Do some combinations of species co-exist whilst others don't? As well as being of interest in ecology and evolution, we also learn more about the biological control of pest species, the management of diseases, the effects of species invasions on communities and the impact of climate change on species distributions and extinction.

Orkney islands
Winter moth larva

In future, this approach will be adapted to other systems, including mosquito-malaria interactions and the evolution of senescence in a nematode worm. The principles that we investigate in the laboratory are also being explored in the natural world. I am currently investigating the ecology and molecular biology of viruses in Lepidoptera and the relative role of horizontal and vertical transmission strategies. I am also exploring interactions between biotic factors (resource limitation, natural enemies) and abiotic factors (environmental variation, land use) that affect winter moth ecology on the Orkney Islands. This pest species is a problem when it destroys the habitat of sensitive ground-nesting birds. Colleagues and I are also working on a multi-disciplinary project that assesses the costs and benefits of organic agriculture at a range of spatial scales across the UK.

Funding from these projects comes from NERC, a joint research council initiative (the Rural Economy & Land Use programme) and The Leverhulme Trust.

 

Current Projects

Current funded projects include;
  • The significance of invasion and the role of natural enemies in shaping insect community assemblages
  • The effects of environmental variation on the ecology and evolution of insect-natural enemy interactions
  • The trade-offs to virus resistance in insect host life history traits, such as development, reproductive fitness and immune responses
  • The ecological and evolutionary consequences of infection by the intracellular parasite Wolbachia in lepidopteran hosts
 

Faculty Research and Innovation


Studentship information

Postgraduate studentship areas:

  • Population and community ecology of insect multi-species interactions.

See also:

Admin roles

External Examiner (taught course): Liverpool
External Examiner (taught course): Cardiff
FBS UGTSEC
UG Programme Leader: Ecology

Modules managed

BLGY5153M - African Field Ecology
BLGY5191M - Biodiversity and Conservation MSc and MRes Summer Project
BLGY5198M - Biodiversity and Conservation MRes Research Project 1

Modules taught

BLGY1117 - Ecology in a Changing World
BLGY1235 - Lives of Carnivores
BLGY1304 - Research Exp. Skills Level 1
BLGY2144 - Population and Community Ecology
BLGY2301 - Research Experience and Skills Level 2
BLGY3133 - Advanced topics in Ecology
BLGY3241 - Conservation Biology
BLGY3340 - Biology Research Projects
BLGY3398 - Research Project and manuscript
BLGY5153M - African Field Ecology
BLGY5190M/5191M - Biodiversity projects
BLGY5191M - Biodiversity and Conservation MSc and MRes Summer Project
BLGY5380M - Extended Research Project

Committees

Member of Undergraduate School Taught Student Education Committee

Centre membership: The Earth and Biosphere Institute

Group Leader Dr Steven Sait  (Reader in Ecology)

Population, community and evolutionary ecology 


Postgraduates

Joseph Hicks  
Stewart Jennings  
Thomas Leech  
Laurin McDowall  
Gorm Shackelford  
Peter Steward  

Savory FR; Benton TG; Varma V; Hope IA; Sait SM Stressful environments can indirectly select for increased longevity. Ecol Evol 4 1176-1185, 2014
DOI:10.1002/ece3.1013
View abstract

Shackelford G; Steward PR; Benton TG; Kunin WE; Potts SG; Biesmeijer JC; Sait SM Comparison of pollinators and natural enemies: a meta-analysis of landscape and local effects on abundance and richness in crops. Biol Rev Camb Philos Soc 88 1002-1021, 2013
DOI:10.1111/brv.12040
View abstract

Gabriel D; Sait SM; Kunin WE; Benton TG Food production vs. biodiversity: comparing organic and conventional agriculture JOURNAL OF APPLIED ECOLOGY 50 355-364, 2013
DOI:10.1111/1365-2664.12035

Backhouse A; Sait SM; Cameron TC Multiple mating in the traumatically inseminating Warehouse pirate bug, Xylocoris flavipes: effects on fecundity and longevity. Biol Lett 8 706-709, 2012
DOI:10.1098/rsbl.2012.0091
View abstract

Sutherland L-A; Gabriel D; Hathaway-Jenkins L; Pascual U; Schmutz U; Rigby D; Godwin R; Sait SM; Sakrabani R; Kunin WE; Benton TG; Stagl S The 'Neighbourhood Effect': A multidisciplinary assessment of the case for farmer co-ordination in agri-environmental programmes Land Use Policy 29 502-512, 2012
DOI:10.1016/j.landusepol.2011.09.003
View abstract

Leggett HC; Jones EO; Burke T; Hails RS; Sait SM; Boots M Population genetic structure of the winter moth, Operophtera brumata Linnaeus, in the Orkney Isles suggests long-distance dispersal ECOL ENTOMOL 36 318-325, 2011
DOI:10.1111/j.1365-2311.2011.01275.x

Lewis Z; de Crespigny FEC; Sait SM; Tregenza T; Wedell N Wolbachia infection lowers fertile sperm transfer in a moth BIOL LETTERS 7 187-189, 2011
DOI:10.1098/rsbl.2010.0605

Savory FR; Sait SM; Hope IA DAF-16 andΔ9 desaturase genes promote cold tolerance in long-lived Caenorhabditis elegans age-1 mutants. PLoS One 6 e24550-, 2011
DOI:10.1371/journal.pone.0024550
View abstract

White SM; Rohani P; Sait SM Modelling pulsed releases for sterile insect techniques: fitness costs of sterile and transgenic males and the effects on mosquito dynamics J APPL ECOL 47 1329-1339, 2010
DOI:10.1111/j.1365-2664.2010.01880.x

Gabriel D; Sait SM; Hodgson JA; Schmutz U; Kunin WE; Benton TG Scale matters: the impact of organic farming on biodiversity at different spatial scales ECOL LETT 13 858-869, 2010
DOI:10.1111/j.1461-0248.2010.01481.x

Collins RM; Afzal M; Ward DA; Prescott MC; Sait SM; Rees HH; Tomsett AB Differential Proteomic Analysis of Arabidopsis thaliana Genotypes Exhibiting Resistance or Susceptibility to the Insect Herbivore, Plutella xylostella PLOS ONE 5 -, 2010
DOI:10.1371/journal.pone.0010103

Niogret J; Sait SM; Rohani P Parasitism and constitutive defence costs to host life-history traits in a parasitoid-host interaction ECOL ENTOMOL 34 763-771, 2009
DOI:10.1111/j.1365-2311.2009.01131.x

Gabriel D; Carver SJ; Durham H; Kunin WE; Palmer RC; Sait SM; Stagl S; Benton TG The spatial aggregation of organic farming in England and its underlying environmental correlates J APPL ECOL 46 323-333, 2009
DOI:10.1111/j.1365-2664.2009.01624.x

Graham RI; Rao S; Sait SM; Attoui H; Mertens PPC; Hails RS; Possee RD Sequence analysis of a reovirus isolated from the winter moth Operophtera brumata (Lepidoptera : Geometridae) and its parasitoid wasp Phobocampe tempestiva (Hymenoptera : Ichneumonidae) VIRUS RES 135 42-47, 2008
DOI:10.1016/j.virusres.2008.02.005

Graham RI; Rao S; Sait SM; Mertens PPC; Hails RS; Possee RD Characterisation and partial sequence analysis of two novel cypoviruses isolated from the winter moth Operophtera brumata (Lepidoptera : Geometridae) VIRUS GENES 35 463-471, 2007
DOI:10.1007/s11262-007-0113-0

Benton TG; Solan M; Travis JMJ; Sait SM Microcosm experiments can inform global ecological problems TRENDS ECOL EVOL 22 516-521, 2007
DOI:10.1016/j.tree.2007.08.003

White SM; Sait SM; Rohani P Population dynamic consequences of parasitised-larval competition in stage-structured host-parasitoid systems OIKOS 116 1171-1185, 2007
DOI:10.1111/j.2007.0030-1299.15750.x

Cameron TC; Metcalfe D; Beckerman AP; Sait SM Intraspecific competition: The role of lags between attack and death in host-parasitoid interactions ECOLOGY 88 1225-1231, 2007

Cameron TC; Wearing HJ; Rohani P; Sait SM Two-species asymmetric competition: effects of age structure on intra- and interspecific interactions J ANIM ECOL 76 83-93, 2007
DOI:10.1111/j.1365-2656.2006.01185.x

Burden JP; Possee RD; Sait SM; King LA; Hails RS Phenotypic and genotypic characterisation of persistent baculovirus infections in populations of the cabbage moth (Mamestra brassicae) within the British Isles ARCH VIROL 151 635-649, 2006
DOI:10.1007/s00705-005-0657-z

Graham RI; Rao SJ; Possee RD; Sait SM; Mertens PPC; Hails RS Detection and characterisation of three novel species of reovirus (Reoviridae), isolated from geographically separate populations of the winter moth Operophtera brumata (Lepidoptera : Geometridae) on Orkney J INVERTEBR PATHOL 91 79-87, 2006
DOI:10.1016/j.jip.2005.11.003

Cameron T; Wearing HJ; Rohani P; Sait SM A koinobiont parasitoid mediates competition and generates additive mortality in healthy host populations Oikos 110 620-628, 2005
DOI:10.1111/j.0030-1299.2005.13964.x

Bonsall MB; Sait SM; Hails RS Invasion and dynamics of covert infection strategies in structured insect-pathogen populations J ANIM ECOL 74 464-474, 2005
DOI:10.1111/j.1365-2656.2005.00945.x

Wearing HJ; Rohani P; Cameron TC; Sait SM The dynamical consequences of developmental variability and demographic stochasticity for host-parasitoid interactions. Am Nat 164 543-558, 2004
DOI:10.1086/424040
View abstract

Graham RI; Tyne WI; Possee RD; Sait SM; Hails RS Genetically variable nucleopolyhedroviruses isolated from spatially separate populations of the winter moth Operophtera brumata (Lepidoptera : Geometridae) in Orkney J INVERTEBR PATHOL 87 29-38, 2004
DOI:10.1016/j.jip.2004.06.002

Wearing H; Sait SM; Cameron T; Rohani P Stage-structured competition and the cyclic dynamics of host-parasitoid populations Journal of Animal Ecology 73 706-722, 2004
DOI:10.1111/j.0021-8790.2004.00846.x

Boots M; Greenman J; Ross D; Norman R; Hails R; Sait SM The population dynamical implications of cover infections in host-microparasite interactions Journal of Animal Ecology 72 1064-1072, 2003
DOI:10.1046/j.1365-2656.2003.00777.x

Burden JP; Nixon CP; Hodgkinson AE; Possee RD; Sait SM; King LA; Hails RS Covert infections as a mechanism for long term persistence of baculoviruses Ecology Letters 6 524-531, 2003
DOI:10.1046/j.1461-0248.2003.00459.x

Rohani P; Wearing H; Cameron T; Sait SM Natural enemy specialization and the period of population cycles Ecology Letters 6 381-384, 2003
DOI:10.1046/j.1461-0248.2003.00437.x

Griffiths CM; McVean RIK; Benmayor R; Sait SM; Thompson DJ; Possee RD; Cory JS; Begon M Host dynamics and pathogen variation in insect-baculovirus interactions In Ecological Dynamics of Genes , 2003

Hails RS; Hernandez-Crespo P; Sait SM; Donnelly CA; Green BM; Cory JS Transmission patterns of natural and recombinant baculoviruses ECOLOGY 83 906-916, 2002

Burden JP; Griffiths CM; Cory JS; Smith P; Sait SM Vertical transmission of sublethal granulovirus infection in the Indian meal moth, Plodia interpunctella Molecular Ecology 11 547-555, 2002
DOI:10.1046/j.0962-1083.2001.01439.x

McVean RIK; Sait SM; Thompson DJ; Begon M Effects of resource quality on the population dynamics of the Indian meal moth Plodia interpunctella and its granulovirus OECOLOGIA 131 71-78, 2002
DOI:10.1007/s00442-001-0862-8

McVean RIK; Sait SM; Thompson DJ; Begon M Dietary stress reduces the susceptibility of Plodia interpunctella to infection by a granulovirus. Biological Control 25 81-84, 2002
DOI:10.1016/S1049-9644(02)00048-8

Hernández-Crespo P; Sait SM; Hails RS; Cory JS Behavior of a recombinant baculovirus in lepidopteran hosts with different susceptibilities. Appl Environ Microbiol 67 1140-1146, 2001
DOI:10.1128/AEM.67.3.1140-1146.2001
View abstract

Bjørnstad ON; Sait SM; Stenseth NC; Thompson DJ; Begon M The impact of specialized enemies on the dimensionality of host dynamics. Nature 409 1001-1006, 2001
DOI:10.1038/35059003
View abstract

Chen JH; Sait SM; Takeuchi H; O'Reilly DR; Turner PC; Rees HH Interactions with the host of recombinant baculovirus expressing components of the insect endocrine system - towards environmentally benign biological control. In Endocrine Interactions of Insect Parasites and Pathogens , 2001

Sait SM; Liu WC; Thompson DJ; Godfray HC; Begon M Invasion sequence affects predator-prey dynamics in a multi-species interaction. Nature 405 448-450, 2000
DOI:10.1038/35013045
View abstract

Briggs CJ; Sait SM; Begon M; Thompson DJ; Godfray HCJ What causes generation cycles in populations of stored-product moths? Journal of Animal Ecology 69 352-366, 2000
View abstract

Begon M; Sait SM; Thompson DJ; Zhou X; Bell ED One, two and three-species time series from a host-pathogen-parasitoid system In Chaos in Real Data: Analysis of Non-Linear Dynamics from Short Ecological Time-Series , 2000

Hernandez-Crespo P; Hails RS; Sait SM; Green BM; Carty TM; Cory JS Response of hosts of varying susceptibility to a recombinant baculovirus insecticide in the field BIOL CONTROL 16 119-127, 1999

Sait SM; Gage MJG; Cook PA Effects of a fertility-reducing baculovirus on sperm numbers and sizes in the Indian Meal Moth, Plodia interpunctella FUNCT ECOL 12 56-62, 1998

Bjornstad ON; Begon M; Stenseth NC; Falck W; Sait SM; Thompson DJ Population dynamics of the Indian meal moth: Demographic stochasticity and delayed regulatory mechanisms J ANIM ECOL 67 110-126, 1998

Sait SM; Begon M; Thompson DJ; Harvey JA; Hails RS Factors affecting host selection in an insect host-parasitoid interaction ECOL ENTOMOL 22 225-230, 1997

Cory JS; Hails RS; Sait SM Baculovirus Ecology In The Baculoviruses , 1997

Begon M; Sait SM; Thompson DJ Two's company, three's a crowd: host-pathogen-parasitoid dynamics In Multitrophic Interactions in Terrestrial Systems , 1997

Vasconcelos SD; Cory JS; Wilson KR; Sait SM; Hails RS Modified behavior in Baculovirus-infected lepidopteran larvae and its impact on the spatial distribution of inoculum BIOL CONTROL 7 299-306, 1996

Sait SM; Begon M; Thompson DJ; Harvey JA Parasitism of baculovirus-infected Plodia interpunctella by Venturia canescens and subsequent virus transmission FUNCT ECOL 10 586-591, 1996

Begon M; Sait SM; Thompson DJ Predator-prey cycles with period shifts between two- and three-species systems NATURE 381 311-315, 1996

BEGON M; SAIT SM; THOMPSON DJ PERSISTENCE OF A PARASITOID-HOST SYSTEM - REFUGES AND GENERATION CYCLES P ROY SOC LOND B BIO 260 131-137, 1995

SAIT SM; ANDREEV RA; BEGON M; THOMPSON DJ; HARVEY JA; SWAIN RD VENTURIA CANESCENS PARASITIZING PLODIA-INTERPUNCTELLA - HOST VULNERABILITY - A MATTER OF DEGREE ECOL ENTOMOL 20 199-201, 1995

SAIT SM; BEGON M; THOMPSON DJ LONG-TERM POPULATION-DYNAMICS OF THE INDIAN MEAL MOTH PLODIA-INTERPUNCTELLA AND ITS GRANULOSIS-VIRUS J ANIM ECOL 63 861-870, 1994

SAIT SM; BEGON M; THOMPSON DJ THE EFFECTS OF A SUBLETHAL BACULOVIRUS INFECTION IN THE INDIAN MEAL MOTH, PLODIA-INTERPUNCTELLA J ANIM ECOL 63 541-550, 1994

MORRISEY DJ; SAIT SM; LITTLE C; WILSON RS THE BENTHIC ECOLOGY OF RIVER ESTUARIES ENTERING THE SEVERN ESTUARY BIOL J LINN SOC 51 247-251, 1994

SAIT SM; BEGON M; THOMPSON DJ THE INFLUENCE OF LARVAL AGE ON THE RESPONSE OF PLODIA-INTERPUNCTELLA TO A GRANULOSIS-VIRUS J INVERTEBR PATHOL 63 107-110, 1994