I am a wildlife ecologist interested in the challenges faced by conservation science in low-income countries, mainly in the Afrotropics. Birds are my preferred model taxon and I have an ongoing research strand on the ecology and conservation of the heavily traded African Grey Parrots (genus Psittacus).

Other research interests include the theoretical and practical aspects of estimating species abundance, and modelling population dynamics of endangered species. 

Thoday Building, room G1

Email: s.valle@bangor.ac.uk

Tel: 01248 382365

LinkedIn profile

ResearchGate profile

• Professional: Fellow of the Higher Education Academy
  Higher Education Academy, 2021–2021
• PhD: Population viability and conservation of Grey Parrots on the island of Príncipe, Gulf of Guinea
  Manchester Metropolitan University, 2012–2015
• MSc: Effects of disturbance and fragmentation on avian community on Afrotropical montane rainforest of the Albertine Rift
  University of Exeter, 2009–2010
• BSc: Composition, phenology, and distribution of the avifauna of the Sabaki, River Mouth, Malindi, Kenya
  University La Sapienza of Rome, 2007

I am course director for the degrees Environmental Conservation (D447/448) and Applied Terrestrial and Marine Ecology (C180/183).

I teach the modules:

DXX-2009: Conservation Practice

DXX-4016: Conservation Science

BNS-3000: Wildlife Ecology and Conservation

DXX-2012:  Field Course on Conservation Conflicts 

2025

• PublishedHeightened extinction risk due to tropical cyclones in insular biodiversity hotspots
  Valle, S., Pereira, D., Matthews, T. J. & Martin, T., 1 Jul 2025, In: Biological Conservation. 307, 111184.
  Research output: Contribution to journal › Article › peer-review
• E-pub ahead of printNew records of Fox's Weaver Ploceus spekeoides significantly disrupt perceptions concerning its conservation status
  Onongo, J., Byaruhanga, A., Nalwanga, D. W., Kibuule, M., Collar, N. J. & Valle, S., 9 Mar 2025, (E-pub ahead of print) In: Ostrich - Journal of African Ornithology. 96, 1, p. 10-16 7 p.
  Research output: Contribution to journal › Article › peer-review

2024

• PublishedA review of bovine tuberculosis transmission risk in European wildlife communities
  Justus, W., Valle, S., Barton, O., Gresham, A. & Shannon, G., 1 Mar 2024, In: Mammal Review. 54, 3, p. 325-340 16 p.
  Research output: Contribution to journal › Article › peer-review
• PublishedDeveloping a method for assessing the relative abundance of red squirrels in low-density populations
  Shannon, G., Barton, O., Valle, S. & Shuttleworth, C., 1 Nov 2024, 34 p.
  Research output: Book/Report › Commissioned report

2023

• PublishedCapturing red squirrels (Sciurus vulgaris) on camera: A cost-effective approach for monitoring relative abundance and habitat preference
  Shannon, G., Valle, S. & Shuttleworth, C., 3 Oct 2023, In: Ecology and Evolution. 13, 10, e10536.
  Research output: Contribution to journal › Article › peer-review

2021

• PublishedRecalibrating Risk: Implications of squirrelpox virus for successful red squirrel translocations within mainland UK
  Shuttleworth, C., Brady, D., Cross, P., Gardner, L., Greenwood, A., Jackson, N., McKinney, C., Robinson, N., Trotter, S., Valle, S., Wood, K. & Hayward, M., Feb 2021, In: Conservation Science and Practice. 3, 2, e321.
  Research output: Contribution to journal › Article › peer-review
• PublishedWhat can the abundance of Grey Parrots on Príncipe Island tell us about large parrot conservation?
  Valle, S., Collar, N. J., Melo, M. & Marsden, S. J., 2021, In: Journal of Tropical Ecology. 36, 6, p. 293- 297
  Research output: Contribution to journal › Article › peer-review

2020

• PublishedLow abundance of the Endangered timneh parrot Psittacus timneh in one of its presumed strongholds
  Valle, S., Collar, N., Barca, B., Dauda, P. & Marsden, S., Jan 2020, In: Oryx. 54, 1, p. 74-76 3 p.
  Research output: Contribution to journal › Article › peer-review

2018

• PublishedTrapping method and quota observance are pivotal to population stability in a harvested parrot
  Valle, S., Collar, N., W. Edwin, H. & Marsden, S., Jan 2018, In: Biological Conservation. 217, p. 428-436
  Research output: Contribution to journal › Article › peer-review

2017

• PublishedSpatial and seasonal variation in abundance within an insular grey parrot population
  Valle, S., Collar, N. J., Harris, W. E. & Marsden, S. J., Dec 2017, In: African Journal of Ecology. 55, 4, p. 433-442
  Research output: Contribution to journal › Article › peer-review

2016

• PublishedPopulation estimates of the breeding birds of the Tinhosas Islands (Gulf of Guinea), the only major seabird colony of the Eastern Tropical Atlantic
  Valle, S., Barros, N., Ramirez, I. & Wanless, R. M., 2016, In: Ostrich - Journal of African Ornithology. 87, 3, p. 209-215
  Research output: Contribution to journal › Article › peer-review

2015

• PublishedUsing encounter rates as surrogates for density estimates makes monitoring of heavily-traded grey parrots achievable across Africa
  Marsden, S. J., Loqueh, E., Takuo, J. M., Hart, J. A., Abani, R., Ahon, D. B., Annorbah, N. N. D., Johnson, R. & Valle, S., 2015, In: Oryx. 50, 4, p. 617-625
  Research output: Contribution to journal › Article › peer-review

2014

• PublishedInternational Action Plan For conservation of Critically Endangered birds on São Tomé
  BirdLife International, Ndang'ang'a, P. K. (Editor), Ward-Francis, A. (Editor), Costa, L. (Editor), Valle, S. (Editor), Lima, R. (Editor), Palmeirim, J. (Editor), Tavares, J. (Editor), Buchanan, G. (Editor), Carvalho, M. (Editor), de Melo, M. (Editor) & Dallimer, M. (Editor), 2014, BirdLife International, Cambridge, UK. 26 p.
  Research output: Book/Report › Commissioned report
• PublishedResearch and conservation of the larger parrots of Africa and Madagascar: a review of knowledge gaps and opportunities
  Martin, R. O., Perrin, M. R., Boyes, R. S., Abebe, Y. D., Annorbah, N. D., Asamoah, A., Bizimana, D., Bobo, K. S., Bunbury, N., Brouwer, J., Diop, M. S., Ewnetu, M., Fotso, R. C., Garteh, J., Hall, P., Holbech, L. H., Madindou, I. R., Maisels, F., Mokoko, J. & Mulwa, R. & 7 others, Reuleaux, A., Symes, C., Tamungang, S., Taylor, S., Valle, S., Waltert, M. & Wondafrash, M., 2014, In: Ostrich: Journal of African Ornithology. 85, 3, p. 205-233
  Research output: Contribution to journal › Article › peer-review
• PublishedSingle Species Action Plan for the conservation of the Príncipe Thrush Turdus xanthorhynchus.
  BirdLife International, Ndang'ang'a, P. K. (Editor), de Melo, M. (Editor), Lima, R. (Editor), Costa, L. (Editor), Buchanan, G. (Editor), Dallimer, M. (Editor), Tavares, J. (Editor), Valle, S. (Editor) & Ward-Francis, A. (Editor), 2014, BirdLife International, Cambridge, UK. 14 p.
  Research output: Book/Report › Commissioned report
• PublishedStatus and trends of the seabirds breeding at Tinhosa Grande Island, São Tomé e Príncipe
  Valle, S., Barros, N. & Wanless, R., 2014, BirdLife International, Cambridge, UK. 27 p.
  Research output: Book/Report › Commissioned report

2013

• PublishedA protocol to allow density estimation and monitoring of the heavily traded grey parrots across their huge African ranges
  Marsden, S. J., Loqueh, E., Takuo, J. M., Hart, J. A., Abani, R., Ahon, D. B., Showers, C., Annorbah, N., Johnson, R. & Valle, S., 2013, Strengthening Capacity for Monitoring and Regulation of International Trade of African Grey Parrot. CITES Secretariat (ed.). CITES Secretariat, p. 1-18
  Research output: Chapter in Book/Report/Conference proceeding › Chapter

2012

• PublishedSeasonal changes in abundances of waterbirds at Sabaki River Mouth (Malindi, Kenya), a key stopover site on the West Asian-East African Flyway
  Valle, S., Boitani, L. & Maclean, I. M. D., 2012, In: Ostrich: Journal of African Ornithology. 83, 1, p. 19-26
  Research output: Contribution to journal › Article › peer-review

2022

• Using remote activated cameras to estimate relative abundance and habitat preference of red squirrels

  Population estimates are essential for the conservation of wildlife. However, accurate estimates can be labour-intensive, particularly for small and medium-sized mammals where capture and handling of individuals is often required. Our study aimed to provide a robust and standardised method of determining red squirrel abundance using remotely activated cameras, while also quantifying how red squirrel abundance relates to key habitat characteristics. Fifty sample points were selected in four habitat categories in forests across Anglesey. We found a strong correlation (r = 0.78) between the number of red squirrels live-trapped over ten-days with the number of camera images recorded during a five-day period. Red squirrel abundance was negatively related to stand canopy openness, while the presence of Scots pine and increased tree species diversity were positively related to squirrel abundance. Our results demonstrate that remotely activated cameras can provide a suitable tool for surveying red squirrel abundance and guiding habitat management.

  19 Dec 2022

  Activity: Oral presentation (Speaker)
• IUCN Conservation Planning Specialist Group (External organisation)

  2022

  Activity: Membership of network (Member)

2019

• External Examiner at the Periodic Programme Review of the Graduate Certificate in Endangered Species Management provided by Durrell Conservation Academy (Durrell Wildlife Conservation Trust)

  21 Mar 2019 – 22 Mar 2019

  Activity: Consultancy (Consultant)

2018

• Ecology and Conservation of the African Grey Parrots

  26 Jul 2018

  Activity: Invited talk (Speaker)
• Timneh Parrot Psittacus timneh population monitoring

  26 Apr 2018

  Activity: Participation in Academic workshop, seminar, course (Speaker)
• Timneh Parrot Psittacus timneh population monitoring

  21 Mar 2018 – 23 Mar 2018

  Activity: Participation in Academic workshop, seminar, course (Speaker)