New eDNA Programme Makes Conservation Research Faster and More Efficient

Posted on August 2, 2019 by Chris Grieves

Below is a press release about the Methods in Ecology and Evolution article ‘Anacapa Toolkit: An environmental DNA toolkit for processing multilocus metabarcode datasets‘ taken from UCLA.

It’s estimated that a person sheds between 30,000 to 40,000 skin cells per day. These cells and their associated DNA leave genetic traces of ourselves in showers, dust — pretty much everywhere we go.

Other organisms shed cells, too, leaving traces throughout their habitats. This leftover genetic material is known as environmental DNA, or eDNA. Research using eDNA began about a decade ago, but was largely limited to a small cadre of biologists who were also experts in computers and big data. However, a new tool from UCLA could be about to make the field accessible and useful to many more scientists.

A team of UCLA researchers recently launched the Anacapa Toolkit — open-source software that makes eDNA research easier, allowing researchers to detect a broad range of species quickly and producing sortable results that are simple to understand. Continue reading →

Conservation or Construction? Deciding Waterbird Hotspots

Posted on July 31, 2019 by Chris Grieves

Below is a press release about the Methods in Ecology and Evolution article ‘A comparative analysis of common methods to identify waterbird hotspots‘ taken from Michigan State University.

A mixed flock of waterbirds on the shore of Lake St. Clair. ©Michigan DNR

Imagine your favourite beach filled with thousands of ducks and gulls. Now envision coming back a week later and finding condos being constructed on that spot. This many ducks in one place surely should indicate this spot is exceptionally good for birds and must be protected from development, right?

It depends, say Michigan State University researchers.

In a new paper published in Methods in Ecology and Evolution, scientists show that conservation and construction decisions should rely on multiple approaches to determine waterbird “hotspots,” not just on one analysis method as is often done. Continue reading →

Life-Long Mosquito Marking: Are Stable Isotopes the Key?

Posted on July 29, 2019 by Chris Grieves

Post provided by ROY FAIMAN

Importance of Marking (Wild) Mosquitoes

Dr. Dao (crouching on right) and team with Dr. Tovi Lehmann (with sandals), Dr. Yaro (with white cap), and Moussa Diallo (front).

The fact that mosquitoes are insects of massive importance is of little dispute. With malaria still killing almost half a million people annually and after recent outbreaks of Zika, dengue and West-Nile viruses the threat of mosquito-borne diseases is becoming common knowledge. The meme of ‘Mosquitoes are the No.1 killer of all time,’ is also growing more popular (I even heard it from my 8-year-old kid one day after he returned from school!). Yet, with all we think we know about the little bug(ger)s, it’s probably only the tip of the iceberg.

Much work was done over the past century to try to answer basic questions about mosquitoes like:

How big are their populations?
How long do they live?
Where do they go when we don’t see or feel them?

Different methods have been developed to provide insights and notions on the mosquitoes’ movements, survival, and populations estimates; but the limitations and conditions of these methods mean that our knowledge is still incomplete.

One of the gold-standard tools for answering questions like those above is Mark-Release-Recapture (MRR). It was developed almost a century ago and has been modified and remodified through the years, as different marking technologies became available. Continue reading →

A More Reliable Method for Estimating Abundance: Close-Kin Mark-Recapture

Posted on July 16, 2019 by Chris Grieves

Post provided by DANIEL RUZZANTE

Knowing how many individuals there are in a population is a fundamental objective in ecology and conservation biology. But estimating abundance is often extremely difficult. It’s particularly difficult in the management of exploited marine, anadromous and freshwater populations. In marine fisheries, abundance estimation traditionally relies on demographic models, costly and time consuming mark recapture (MR) approaches if they are feasible at all, and the relationship between fishery catches and effort (catch per unit effort or CPUE). CPUEs can be subject to bias and uncertainty. This is why they tend to be considered relatively unreliable and contentious.

Close-Kin Mark-Recapture: Reducing Bias and Uncertainty

There is an alternative method though. It’s known as “Close-Kin Mark-Recapture” (CKMR), and is grounded in genomics and was first proposed by Skaug in 2001. The method is based on the principle that an individual’s genotype can be considered a “recapture” of the genotypes of each of its parents. Assuming the sampling of offspring and parents is independent of each other, the number of Parent-Offspring pairs (POP) genetically identified in a large collection of both groups can be used to estimate abundance. Continue reading →

Using Molecular Power to Reconstruct Hyperdiverse Food Webs

Posted on June 11, 2019 by Chris Grieves

Post provided by JORDAN CASEY

Coral Reefs: The Ocean’s Most Extravagant Buffet

Coral reefs are home to an incredibly diverse array of species ©Jordan Casey

There are an estimated 830,000 species on coral reefs worldwide. At some stage in their lives, nearly all of these species are consumed as prey items. In this super diverse buffet of fishes, corals, crabs, worms, and other critters, the number of possible interactions between predators and prey is nearly inexhaustible.

The extreme diversity of coral reefs has fascinated naturalists for centuries. Pinpointing predator-prey dynamics is essential to fully understand coral reef ecosystem dynamics, and visual analysis of gut contents has been a staple technique of coral reef ecologists. While the joy of spending copious hours looking through a microscope at half-digested marine mush is undeniable, this type of visual inspection has limitations. Even so, visual gut content analysis (along with stable isotope analysis and behavioural observations) has showcased a highly complex dietary network.

To digest this extreme complexity and surmount the hurdle of dietary unknowns, researchers frequently lump fishes into broad trophic categories, such as ‘mobile herbivores’. Broad generalisations are pragmatic and may be help us detect broad ecological trends, but they oversimplify species’ actual dietary preferences. As coral reefs are changing due to anthropogenic disturbances, it’s critical to thoroughly examine how well trophic groupings capture dietary linkages among reef organisms. Continue reading →

Assessing Sea Turtle Populations: Can We Get a Hand From Drones and Deep Learning?

Posted on May 23, 2019 by Chris Grieves

Post provided by PATRICK GRAY

An olive ridley sea turtle in Ostional, Costa Rica. ©Vanessa Bézy.

Understanding animal movement and population size is a challenge for researchers studying any megafauna species. Sea turtles though, add a whole additional level of complexity. These wide-ranging, swift, charismatic animals spend much of their time underwater and in remote places. When trying to track down and count turtles, this obstacle to understanding population size becomes a full-on barricade.

Censusing these animals doesn’t just satisfy our scientific curiosity. It’s critical for understanding the consequences of unsound fishing practices, the benefits of conservation policy, and overall trends in population health for sea turtles, of which, six out of seven species range from vulnerable to critically endangered. Continue reading →

Where do Animals Spend Their Time and Energy? Theory, Simulations and GPS Trackers Can Help Us Find Out

Posted on May 22, 2019 by Chris Grieves

Post provided by MATT MALISHEV (@DARWINANDDAVIS)

An adult sleepy lizard with a GPS tracker and body temperature logger strapped to her tail. ©Mike Bull.

Changes in temperature and available food determine where and when animals move, reproduce, and survive. Our understanding of how environmental change impacts biodiversity and species survival is well-established at the landscape, country and global scales. But, we know less about what could happen at finer space and time scales, such as within habitats, where behavioural responses by animals are crucial for daily survival.

Simulating Movement and Daily Survival with Individual-Based Movement Models

Key questions at these scales are how the states of individuals (things like body temperature and nutritional condition) influence movement decisions in response to habitat change, and how these decisions relate to patchiness in microclimates and food. So we need tools to make reliable forecasts of how fine-scale habitat use will change under future environments. Individual-based movement simulation models are powerful tools for these kinds of studies. They let you construct habitats that vary in temperature and food conditions in both space and time and ask ‘what if’ questions. By populating these models with activity, behaviour, and movement data of animals, we can simulate different habitat conditions and predict how animals will respond to future change. Continue reading →

Scant Amounts of DNA Reveal Conservation Clues

Posted on May 9, 2019 by Chris Grieves

Below is a press release about the Methods in Ecology and Evolution article ‘Empowering conservation practice with efficient and economical genotyping from poor quality samples‘ taken from the Stanford Woods Institute for the Environment.

The challenges of collecting DNA samples directly from endangered species makes understanding and protecting them harder. A new approach promises cheap, rapid analysis of genetic clues in degraded and left-behind material, such as hair and commercial food products.

The key to solving a mystery is finding the right clues. Wildlife detectives aiming to protect endangered species have long been hobbled by the near impossibility of collecting DNA samples from rare and elusive animals. Continue reading →

Volunteer Ornithological Survey Shows Effects of Temperatures on Eurasian Jay Population

Posted on April 26, 2019 by Chris Grieves

Below is a press release about the Methods in Ecology and Evolution article ‘Incorporating fine‐scale environmental heterogeneity into broad‐extent models‘ taken from the University of Southampton.

A study led by researchers at the University of Southampton has used data collected by volunteer bird watchers to study how the importance of wildlife habitat management depends on changing temperatures for British birds.

The team studied data from the British Trust for Ornithology’s Bird Atlas 2007 – 11 on the abundance of the Eurasian jay over the whole of Great Britain. The University of Southampton researchers focused on jays for this trial as they are a species of bird known to frequent a mixture of different natural environments. Continue reading →

Studying Wild Bats with Small On-Board Sound and Movement Recorders

Posted on April 17, 2019 by Chris Grieves

Post provided by LAURA STIDSHOLT

Releasing a female Greater mouse-eared bat with the tag in collaboration with Holger Goerlitz, Stefan Greif and Yossi Yovel. ©Stefan Greif

The way that bats acrobatically navigate and forage in complete darkness has grasped the interest of scientists since the 18^th century. These seemingly exotic animals make up one in four mammalian species and play important roles in many ecosystems across the globe from rainforests to deserts. Yet, their elusive ways continue to fascinate and frighten people even today. Over the last 200 years, dedicated scientists have worked to uncover how bats hunt and navigate using only their voice and ears while flying at high speed in complete darkness. Still, the inaccessible lifestyle of these small, nocturnal fliers continues to challenge what we know about their activities in the wild.

Understanding the impact bats have on their ecosystems – for example how many insects a bat catches per night – has still not been directly measured. Most of our knowledge on the natural behaviour and foraging ecology is based on elaborate, but ground-based experiments carried out in the wild. These experiments generally track their behaviour using radio-telemetry, record snapshots of their emitted echolocation calls with microphones, or involve extensive observations. Continue reading →

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