All You (Possibly) Ever Wanted to Know about ‘Trap Nests’

Post provided by Michael Staab

What are ‘Trap Nests’ and What are They Good For?

Females are attracted to the hollow material in trap nests.

Females are attracted to the hollow material in trap nests.

When thinking of bees and wasps, most people have social insects living in colonies in mind. But most species are actually solitary. In these species, every female builds her own nest and does not care for the offspring once nest construction is completed. Most of those species nest in the ground. Several thousand species of bees and wasps use pre-existing above-ground cavities though (such as hollow twigs and stems, cracks under bark, or empty galleries of wood-boring insects).

To keep you in suspense, I’ll resolve the importance of studying cavity-nesting species later in this blog post. First, I’ll introduce you to one of the more elegant research methods in ecology: trap nests. To study and collect these cavity-nesting species, you can take advantage of their nesting preferences. By exposing artificial cavities and offering access to an otherwise restricted nesting resource, you can attract females searching for suitable nesting sites.

Building these trap nests is simple, but the design can vary greatly. Many designs and materials can be used to build the artificial nesting sites, such as drilling holes in wooden blocks or packing hollow plant material (e.g. reeds) in plastic tubes. Once females find the trap nest and finish their nest construction, the developing offspring are literally ‘trapped’ in their nests. They can then be collected, their trophic interactions (e.g. food and natural enemies) observed, and the specimens can be reared for identification. Continue reading

How Many Animals are Infected with Chronic Wasting Disease?

Post provided by Hildegunn Viljugrein

©Alexandre Buisse

©Alexandre Buisse

The discovery of Chronic Wasting Disease (CWD) in Norway in 2016 has led to extensive measures and testing of deer in Norway. Since 2018 there have been similar measures within the EU. But how many deer need to be tested before we can be (almost) certain that a population is not infected by CWD?

In our article – ‘A method that accounts for differential detectability in mixed samples of long‐term infections with applications to the case of Chronic Wasting Disease in cervids’ – we provide important tools for estimation of prevalence and likelihood of finding infected animals in a given population. The paper is a result of a collaborative work between a multidisciplinary group of scientists from the Norwegian Veterinary Institute, Norwegian Institute for Nature Research and Prof. Atle Mysterud from Centre for Ecological and Evolutionary Synthesis at the University of Oslo. Continue reading

Spatial Capture-Recapture: The Pros and Cons of Aggregating Detections

Post provided by Cyril Milleret

Spatial Capture-Recapture and Computation Time

SCR models simultaneously estimate the detection function and density of individual activity centres. A half-normal detection model is generally used.

SCR models simultaneously estimate the detection function and density of individual activity centres. A half-normal detection model is generally used.

The estimation of population size is one of the primary goals and challenges in wildlife ecology. Within the last decade and a half, a new class of tools has emerged, allowing us to estimate abundance and other key population parameters in specific areas. So-called spatial capture-recapture (SCR) models are growing in popularity not only because they can map abundance, but also because they can be fitted to data collected from a variety of monitoring methods. For example, the ever increasing use of non-invasive monitoring methods, such as camera trapping and non-invasive genetic-sampling, is one of the reason that makes SCR models so popular.

One other strengths of SCR models is the ability to make population level inferences. But the wider the region you’re monitoring, the greater the computational burden, challenging the use of such methods at really large scale. Continue reading

What the Past Can Tell Us About the Future: Notes from Crossing the Palaeontological – Ecological Gap

Post provided by Karen Bacon

I had the pleasure of delivering one of the plenary talks at the first (hopefully of many) Crossing the Palaeontological – Ecological Gap meeting held in the University of Leeds on August 30th and 31st. I’m a geologist and a botanist, so this is a topic that’s close to my heart and my professional interests.

How Palaeoecology Can Help Us Today

©Gail Hampshire

©Gail Hampshire

As we move into an ecologically uncertain future with pressures of climate change, land-use change and resource limitations, the fossil record offers the only truly long-term record of how Earth’s ecosystems respond to major environmental upheaval driven by climate change events. The fossil record is, of course, not without its problems – there are gaps, not everything fossilises in the same way or numbers, and comparisons to today’s ecology are extremely difficult.  It’s these difficulties (and other challenges) that make the uniting of palaeontology and ecology essential to fully address how plants, animals and other organisms have responded to major changes in the past. Perhaps uniting them could give us an idea of what to expect in our near-term future, as carbon dioxide levels return to those not previously experienced on Earth since the Pliocene, over 2 million years ago. Continue reading

The Manager’s Dilemma: Which Species to Monitor?

Post provided by Payal Bal and Jonathan Rhodes

The greater bilby (M.Lagotis). ©Save the Bilby Fund

The greater bilby (M.Lagotis). ©Save the Bilby Fund

Imagine you’re the manager of a national park. One that’s rich in endemic biodiversity found nowhere else on the planet. It’s under the influence of multiple human pressures causing irreversible declines in the biodiversity, possibly even leading to the extinction of some of the species. You’re working with a complex system of multiple species and threats, limited knowledge of which threats are causing the biggest declines and limited resources. How do you decide what course of action to take to conserve the biodiversity of the park? This is the dilemma faced by biodiversity managers across the globe.

In our recent paper, ‘Quantifying the value of monitoring species in multi‐species, multi‐threat systems’, we address this problem and propose a method using value of information (VOI) analysis. VOI estimates the benefit of monitoring for management decision-making. Specifically, it’s a valuation tool that can be used to disentangle the trade-offs in competing monitoring actions. It helps managers decide how to invest (or whether to invest) their money in monitoring actions when faced with imminent biodiversity declines and the urgency of efficient conservation action. Continue reading

Improving Biodiversity Monitoring using Satellite Remote Sensing

Increased access to satellite imagery and new developments in remote sensing data analyses can support biodiversity conservation targets by stepping up monitoring processes at various spatial and temporal scales. More satellite imagery is becoming available as open data. Remote sensing based techniques to capitalise on the information contained in spatially-explicit species data, such as Global Biodiversity Information Facility (GBIF), are developing constantly. Current free and open data policy will have a dramatic impact on our ability to understand how biodiversity is being affected by anthropogenic pressures, while improving our ability to predict the consequences of changes at different scales.

In our latest Special Feature, ‘Improving Biodiversity Monitoring using Satellite Remote Sensing‘, Sandra Luque, Nathalie Pettorelli, Petteri Vihervaara and Martin Wegmann explain why tackling this challenge is worth doing. The articles demonstrate how combining satellite remote sensing data with ground observations and adequate modelling can help to give us a better understanding of natural systems, leading to improved management practices. They focus on three key conservation challenges:

  1. Monitoring of biodiversity
  2. Developing an improved understanding of biodiversity patterns
  3. Assessing biodiversity’s vulnerability to climate change

Continue reading

Also of Interest… Journal of Applied Ecology

Post provided by Aaron M. Ellison

The Struggle is Real: Finding Interesting and Relevant Articles

Where to start? We are awash in data, information, papers, and books. There are hundreds of ecological and environmental journals published regularly around the world; the British Ecological Society alone publishes five journals and is now accepting submissions for a sixth (more information on People and Nature here).

None of us has time even to click on the various articles flagged by alerts, feeds, or keywords, and few even browse tables of contents (which are becoming irrelevant as we move to DOIs and immediate-online publication). Increasingly, we rely on our friends, colleagues, students, and mentors to point us towards papers we might find interesting – further evidence, I suppose, of the importance of good networks for knowledge creation and scientific understanding.

Regular readers of Methods in Ecology and Evolution or this Methods blog may not realise how many methodological papers are published routinely in our BES sister journals. In this inaugural posting of Also of interest…, I highlight three papers recently published in Journal of Applied Ecology that introduce and apply new, model-based methodology to interesting ecological questions. The specific methods are like many seen in the pages of Methods in Ecology and Evolution and suggest general approaches for modelling and studying complex ecological and environmental phenomena. Continue reading

TV Coverage of Cycling Races Can Help Document the Effects of Climate Change

Archive footage of the Tour of Flanders obtained by Flemish broadcaster VRT - Flanders Classics

Archive footage of the Tour of Flanders obtained by Flemish broadcaster VRT – Flanders Classics

Analysing nearly four decades of archive footage from the Tour of Flanders, researchers from Ghent University have been able to detect climate change impacts on trees. Their findings were published today in the journal Methods in Ecology and Evolution.

Focusing on trees and shrubs growing around recognisable climbs and other ‘landmarks’ along the route of this major annual road cycling race in Belgium, the team looked at video footage from 1981 to 2016 obtained by Flemish broadcaster VRT. They visually estimated how many leaves and flowers were present on the day of the course (usually in early April) and linked their scores to climate data. Continue reading

The Future of Solar Geolocation Tracking is NOW

Post provided by Julia Karagicheva, Theunis Piersma and Eldar Rakhimberdiev

Black-tailed godwit with leg-mounted solar geolocator. ©Jan van de Kam

Black-tailed godwit with leg-mounted solar geolocator. ©Jan van de Kam

Working on FLightR, the package for analysis of data obtained from solar geolocation tracking devices, we were haunted by the unpleasant feeling of investing in technology which will soon be out of date. Until now solar geolocators have been popular in ornithological studies. This is because they’re small, light-weight (< 1/3 g) tracking devices that can be deployed even on miniature birds, such as swallows and warblers. They’ve also been the longest-lasting data loggers, with the most storage space and, of course, the most affordable ones.

Are Solar Geolocators Finished?

There are apparent drawbacks of using this technique though. To begin with, solar geolocation simply does not work for some species. You can’t use it to study birds living in dense tropical forests or in cavities, because of the light-pattern bias. For the same reason, it doesn’t provide fantastic results in light-polluted areas. Data from geolocators cannot be retrieved remotely, and this is why you need to have high recapture rates for the species you’re studying.   Continue reading

Remote Camera Network Tracks Antarctic Species at Low Cost

Below is a press release about the Methods in Ecology and Evolution article ‘Estimating nest‐level phenology and reproductive success of colonial seabirds using time‐lapse cameras‘ taken from NOAA Fisheries.

Camera system in place in an Adélie and gentoo penguin colony ©Jefferson Hinke, NOAA Fisheries

Camera system in place in an Adélie and gentoo penguin colony ©Jefferson Hinke, NOAA Fisheries

An international research team has developed a simple method for using a network of autonomous time-lapse cameras to track the breeding and population dynamics of Antarctic penguins, providing a new, low-cost window into the health and productivity of the Antarctic ecosystem.

The team of scientists from NOAA Fisheries and several other nations published in the journal Methods in Ecology and Evolution, descriptions of the camera system and a new method for turning static images into useful data on the timing and success of penguin reproduction. They say that the system monitors penguins as effectively as scientists could in person, for a fraction of the cost. Continue reading