Author Archives: Eleni Matechou

News, Papers, Publications

New paper by Eleni and colleagues published in JABES

The paper, titled  “Caste-Specific Demography and Phenology in Bumblebees: Modelling BeeWalk Data”, by Eleni Matechou, Stephen N. Freeman, and Richard Comont is available open-access. 

The work presents novel dynamic mixture models for the monitoring of bumblebee populations on an unprecedented geographical scale, motivated by the UK citizen science BeeWalk.

The models allow us for the first time to estimate bumblebee phenology and within-season productivity, defined as the number of individuals in each caste per colony in the population in that year, from citizen science data.

All of these parameters are estimated separately for each caste, giving a means of considerable ecological detail in examining temporal changes in the complex life cycle of a social insect in the wild. Due to the dynamic nature of the models, we are able to produce population trends for a number of UK bumblebee species using the available time-series. Via an additional simulation exercise, we show the extent to which useful information will increase if the survey continues, and expands in scale, as expected.

Bumblebees are extraordinarily important components of the ecosystem, providing pollination services of vast economic impact and functioning as indicator species for changes in climate or land use. Our results demonstrate the changes in both phenology and productivity between years and provide an invaluable tool for monitoring bumblebee populations, many of which are in decline, in the UK and around the world.

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Papers

Model averaging in ecology: a review of Bayesian, information-theoretic and tactical approaches for predictive inference

The review paper, by Dormann, C.F., Calabrese, J.M., Gurutzeta, G., Matechou, E., Bahn, V., Bartoń, K., et al. to appear in Ecological Monographs, explores different model averaging techniques in terms of ways to calculate the model weights and to combine predictions from different models. The advantages and disadvantages of model averaging are discussed and code for methods falling under three categories (Bayesian, information theoretical and tactical) is provided.

Read a blog post written by the main contributors of the paper here.

 

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Uncategorized

NERC Advanced Training Course

Statistical models for wildlife population assessment and conservation

19-23 March 2018

University of Kent

Further details of the workshop and details of how to apply for a place can be found here:

https://www.kent.ac.uk/graduateschool/skills/advancedtraining.html

Please note that the deadline for applications is 1st October 2017.  Successful applicants will be informed in early September.

We have 30 fully-funded places (inc. travel and accommodation) and priority is given to NERC-funded PhD students but if spaces remain we are able to offer the funded places to other PhD students and early-career researchers.

Within the environmental sector there is currently a shortage of practitioners equipped with the statistical modelling skills to carry out reliable population assessments. Consequently, environmental impact assessments (EIAs) and development mitigation projects often use population assessment protocols that are not fit-for-purpose1. The skills shortage arises because (1) recent advances in statistical models for population assessment are largely confined to the academic sector with little penetration to the end-users; and (2) although many postgraduate programmes have a statistical modelling training component, this often fails to expose PhD students to new models in the area and the potential applications these have for conservation practice2. This training programme will provide a cohort of PhD students and early career researchers/practitioners with the relevant modelling skills required for a career that involves wildlife population assessment for conservation.

  1. Griffiths, Foster, Wilkinson and Sewell (2015). Science, statistics and surveys: a herpetological perspective. Journal of Applied Ecology. doi: 10.1111/1365-2664.12463
  2. McCrea and Morgan (2015). Analysis of capture-recapture data. Chapman & Hall/CRC Press, Florida.

 

Proposed programme of the course

The workshop will focus on ecological questions that arise in conservation practice and use real case study data. Training will include individual-based models, such as capture-recapture, but will also embrace scenarios more frequently used in EIA, such as batch-marked, presence/absence, site occupancy and counts. Applications will include newts, butterflies, birds, bees, beetles, ibex and bats. Each module will be accompanied by a practical computer session using R and each module builds on the last so that delegates build a portfolio of statistical skills.

Training outcomes:  By the end of the course, attendees will be able to:

  • construct, interpret and fit relevant stochastic models, use different methods of inference, understand the pros and cons of Bayesian and classical methods and the use of prior information;
  • personalise R code to undertake modelling of their own research data;
  • understand data needs for animal population assessments for EIAs and conservation;
  • analyse animal population data to meet both conservation and commercial needs.

Draft timetable:

Module 1: Background in statistics and R (Monday PM)
  • Likelihood and probability theory
  •  Bayesian inference
  • Basic model assessment (AIC/absolute GOF)
  • Practical session: Introduction
Plenary session and Round table discussions (Tuesday AM)
Module 2: Understanding statistical uncertainty (Tuesday PM)
  • Imperfect detection
  • Data types, relationships and summaries.
  • Introduction to data sets/case studies (bees, butterflies, newts, mallards etc)
  • Practical session: converting format of data and summarising complex data.
Module 3: Model fitting and assessment (Wednesday AM+PM)
  • Estimating abundance
  • M0,Mtbh, removal
  • CR/RR
  • Occupancy
  • Practical session: model fitting, optimisation, use of packages.
Module 4: Modern challenges (Thursday AM)
  • Citizen science data
  • Small/sparse data and big data issues
  •  Cost-effectiveness in study design and statistical power.
  • Informative prior information.
  • Practical session: power analyses and adapting models
Module 5: Advanced stochastic modelling (Thursday PM)
  • modelling movement
  •  state uncertainty
  • species interaction
  • spatial models
  • integrated modelling
  • Practical session: use of Rjags, Bayesian graphical models using MCMC.
One-to-one consultation sessions (Friday AM)
Module 6: Advanced aspects of R (Friday AM)
  • Practical session: self-lead worksheets
  • Multistate examples
  • PR diagnosis
  • Diagnostic GOF testing
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Uncategorized

Eleni gave a seminar at Sheffield

Eleni gave a seminar on the 15th of March 2017 as part of the Ecology, Evolution and Environment seminar series at the Department of Animal and Plant Sciences, University of Sheffield.

Title: Modelling phenology for marked and unmarked populations

Abstract: In this seminar I will discuss fairly recent models for capture-recapture and for count data that enable us to estimate, among other things, phenology of wildlife populations. The methods explored will include classical as well as Bayesian parametric and non-parametric approaches. They will be demonstrated using data on breeding great crested newts, migrating reed warblers, bivoltine butterfly species , bumblebees from the citizen science scheme BeeWalk as well as data on anglers in Norway.

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Conferences/Meetings/Workshops

Ming participated in postgraduate research festival

Ming presented a poster titled “Optimal Design for Removal Sampling” at the postgraduate research festival that took place at the University of Kent.

She presented her work in which she investigates removal models accounting for temporary emigration analytically and examines how to optimally allocate a fixed level of total sampling effort in terms of maximising the Fisher information.

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News

SE@K student Alex Diana doing field work!

First year student Alex Diana and his supervisor, Dr Eleni Matechou, took part in field work sampling for newts.

The long-running project, coordinated by the Durrell Institute for Conservation and Ecology (DICE) at the University of Kent, collects data on newt populations breeding in ponds located near the Canterbury campus.

They saw and identified male and female great crested, palmate and smooth newts. They also learned where newts place their eggs and what male newts do to attract the females (thanks to a very vivid description by Professor Richard Griffiths from DICE!)

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Conferences/Meetings/Workshops

SE@K students run masterclasses for SMSAS

Three SE@K students (Ming, Marina and Alex) took part in masterclasses organised by the SMSAS outreach officer, Joe Watkins. For details about master classes and other outreach events at SMSAS see here https://www.kent.ac.uk/smsas/outreach/on-campus.html.

The classes took place on two days and involved four sessions: i) Introduction to probability and statistics ii) Removal modelling, iii) Occupancy modelling and iv) Capture-recapture modelling. They were attended by some of the most enthusiastic and engaged year 9 students in the local area.

All sessions were interactive and the participating year 9 students had the opportunity to replicate real-life sampling techniques for monitoring populations of lizards, penguins and birds. These involved digging for lizards in the sand, looking for hidden penguins and marking birds. No animals were hurt in the process as they were all made out of plastic!

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Conferences/Meetings/Workshops

NCSE Summer 2017 meeting at the University of Kent

The Statistical Ecology @ Kent (SE@K) group will host the next NCSE summer meeting, which is returning to the University of Kent after 10 years and will take place in the w/c 26th of June 2017.

Click for  Programme and  Abstracts.

The meeting will include an invited talk by Professor Robert P Freckleton, University of Sheffield, and a one-day workshop by Professor David Borchers, University of St Andrews, and Professor Finn Lindgren, University of Edinburgh, on “Spatial Point Process Modelling with INLAbru”.

Meeting Location:

Registration will take place in the foyer of the Grimond building on the University of Kent campus, at 2pm on Monday, 26th June. The talks and workshop will take place in Grimond Lecture Theatre 2 (GLT2). The location indicated can be found on the University map at  https://www.kent.ac.uk/maps/canterbury/canterbury-campus/building/grimond-building/glt2

Drinks Reception:

There will be a drinks reception on Monday at 5.20pm in Grimond Foyer.

Meeting dinner:

The meeting dinner will take place on Tuesday at 7pm.  It will be free for NCSE members, excluding drinks and take place in a private room in Café du Soleil in Canterbury; see www.cafedusoleil.co.uk

Workshop:

On Thursday there will be a workshop  on Spatial Point Process Modelling with INLAbru by David Borchers and Finn Lindgren. Participants in the workshop will need to bring their own laptop and install the packages listed in: workshop preparation

Travel to Canterbury:

A campus map and travel instructions can be found at https://www.kent.ac.uk/maps/canterbury

Accommodation:

There are various possibilities, including Air B&B. The University campus is on a hill outside Canterbury. There are buses regularly connecting the campus to the city, and the walk takes less than 30 minutes each way. General information is to be found at: www.canterbury.co.uk

– We should be able to make a block booking in student accommodation on campus; this is probably going to be an economic option. In order to do this we will need to know how many people would be interested. If you are interested then let us know by the 7 April deadline.

– A B&B at the entrance to the campus is the City of Canterbury: www.thecityofcanterbury.co.uk/

Outing:

Tuesday afternoon will be free for an outing.

The first railway in the world to issue season tickets ran from Canterbury to Whitstable, opening in 1830. We propose a walk along the line of this historic railway (the Crab and Winkle line) for those who may be interested. From the campus the 6-mile walk to Whitstable passes through  woods and  countryside. At Whitstable it would be possible to take refreshment at local pubs around the harbour, and possibly sample Whitstable oysters. If walking back is unattractive then there are regular buses.

The walk will leave Grimond Foyer at 12.30 and go via the campus shop to buy yourself a packed lunch.

There is no shortage of alternative activities for individuals. Canterbury contains a UNESCO World Heritage site, comprising the Cathedral, St Augustine’s Abbey and St. Martin’s church.  See http://www.canterbury.co.uk/things-to-see-and-do. In addition there are possibilities of visiting Faversham, home to Shepherd Neame brewery, Britain’s oldest brewer, and Dover and Leeds castles.

Bird watching is possible at various local sites, including at Stodmarsh Natural Nature Reserve, which we visited when the last NCSE summer meeting was held in Canterbury. This is home to Bearded reedlings, Marsh harriers, Cetti’s warblers, Bitten and many more. The reserve is 20 minutes drive from the campus. Blean woods is walking distance from the campus, and is one of just a few sites in the UK where there is a chance of seeing the rare Heath Fritillary butterfly, weather permitting.

 

 

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