INVASIVE SPECIES AND THE CARP-OCALYPSE

Non-native species are a problem in the environment when they establish new populations and disperse – i.e. become invasive. A highly invasive, global invader of freshwaters is the common carp, a fish capable of reaching weights of over 30 kg as well as producing a large number of offspring, and is proving to be an ecological and economic pest wherever it goes. They are a highly popular species for catch-and-release recreational angling (see Figure 1), as well as being an important species in aquaculture – but this has resulted in their invasion of all continents except Antarctica. They have been invading British freshwaters since at least the Middle Ages and perhaps as early as the Roman Times.

Invasive carp are well known as ecological engineering species, altering the physical habitats of their invaded freshwaters through their aggressive benthic foraging. However, what is less known is the extent of their competitive interactions with native fish species, especially those that have populations which are already threatened with issues such as habitat loss – like the crucian carp, a relatively diminutive fish in the same family as common carp and with similar benthic feeding habits and functional morphology.

Although generating understandings of the interactions of invasive and alien species can be achieved through field studies alone, a major issue with many field studies on invasive species is that they tend to have high context-dependency. For example, while studies provide interesting and useful information, that information is often only insightful to the study site in question due to, for example, issues such as a lack of data prior to the invasion, limited knowledge on the introduction event, the use of one-off sampling events, and a lack of control in the environmental conditions. In combination, this makes it very difficult to draw strong conclusions beyond the study site and species in question. To overcome these issues, in our study we completed two sets of experiments that would help us understand the competitive interactions of the invasive species (common carp) versus the threatened native species (crucian carp) under relatively controlled conditions to understand the processes that might be producing the patterns in our field data. 

The first of these experiments was a set of comparative functional response experiments completed in tank aquaria. As both species shoal, we used the fish in conspecific pairs and at a water temperature that the fish typically experience in Southern Britain during summer (17 oC). We exposed the pairs of fish to a range of prey densities for fixed time intervals to determine their feeding rates. The results showed common carp had much higher feeding rates than crucian carp, suggesting they would monopolise food resources when they are together.

Figure 2. The crucian carp – this small species tends to inhabit ponds which are increasingly invaded by common carp, with our results suggesting the increased inter-specific competition will result in them having to consume a wider range of prey items to survive. ( J. Robert Britton).

This experiment complemented a much larger and longer experiment completed between 2016 and 2019 in a set of three ponds that were drained prior to the experiment (so they started with no fish) and were then seeded with 100 fish of similar sizes into each pond – one with only crucian carp, one with only common carp and one with 50 of each. Although we could not replicate these treatments, we could follow the feeding interactions of the fish across the experiment through the ecological application of stable isotope analysis. We revealed that when only one species was present in a pond, the extent of the food resources each species consumed – their trophic niches – were similar. When they were together, however, the trophic niches of both species were much larger and were very different from each other (they had ‘divergent niches’). These results indicated that their interactions resulted in them having to feed on a much greater range of prey items than when they were separate, with common carp also having to alter their diet – despite being the superior competitor.

These experimental findings were then used to help us interpret the patterns in our field data from four wild ponds where the two species were present together. In all ponds, their trophic niches were also strongly diverged from each other, as per the experimental ponds, and where the comparative functional response data suggested this was driven by the strong competition pressure from common carp.

The use of the two experiments enabled us to identify that the highly invasive species – common carp – is a strong competitor and one that the threatened native species – crucian carp – finds it difficult to compete with. As common carp become more prevalent across the world’s freshwaters, the outcome for fish species already under threat, such as crucian carp, do not look favourable.

This blog post is provided by Victoria Dominguez Almela, Josie South & Robert Britton and tells the #StoryBehindThePaper for the paper ‘Predicting the competitive interactions and trophic niche consequences of a globally invasive fish with threatened native species‘, which was recently published in the Journal of Animal Ecology.

Jane Goodall Roots and Shoots programme and SAMARCH

Last week, Genoveva Esteban and Katie Thompson from SAMARCH hosted two workshops for school children, showcasing SAMARCH research. This was their first workshop as part of Bournemouth University and the Jane Goodall Institute Roots and Shoots programme. Their virtual workshop incorporated a talk on facts about Atlantic salmon, recent research, and interactive elements for the children to get involved in. Their presentation also doubled up as an activity workbook for children to work on from home.

For any questions about the event, or if you are interested in this activity for your school, please contact Katie via email: thompsonk@bournemouth.ac.uk

Restoring Kenya’s most threatened forests

Lindsay Biermann (LEAF)

Across the world, natural ecosystems are becoming increasingly degraded and fragmented. As a consequence, preservation of remaining intact habitats is likely to be insufficient for many species. Instead, the United Nations has identified restoring wild places as a global priority in its upcoming decade on ecosystem restoration.

In response to this, former Bournemouth Life and Environmental Sciences alumnus, Lindsay Biermann, has helped found the Little Environmental Action Foundation (LEAF for short) alongside thirteen fellow young conservationists. LEAF’s mission is to restore some of the most threatened ecosystems across the tropics, whilst using research-driven approaches and 100% native species.

LEAF’s first project is focused on cultivating and planting indigenous trees in coastal Kenya. Situated in the East African Coastal Forest Biodiversity hotspot, this project aims to save the region’s endemic trees that are all predicted to go extinct by 2050 without intervening action. LEAF is working in partnership with Pwani University to recover seeds, grow seedlings and plant out these threatened endemic species around fragments of ancient forest sites called relics. These relics are incredibly important to the future of this region, as currently 96% of native trees have been lost to monoculture plantations and farming.

Using research and expertise, LEAF has begun by employing local graduates and implementing ex situ conservation on the university grounds. From here, we plan to expand our efforts to plant trees close to pre-existing relict sites, educate local people on how to protect these forests and show why their ecosystem services are invaluable. By focusing on native tree species, we aim to increase the survival rates of planted trees and also the long-term recovery of these forests. Collaborative research with university students is also helping to maximise survival rates by studying salt and drought tolerance, as well as optimal planting times.

LEAF is set to officially launch in National Tree week running from 28th November to 6th December. As part of the launch, LEAF is aiming to raise funds to build a new seedling nursery that can propagate and grow rare and endangered tree species. From these donations, LEAF hope to transform the nursery to provide sufficient capacity for future forest restoration projects.

The LEAF charity is remains in its infancy but has ambitious plans to expand its restoration work into ten countries by 2030. Potential projects in Rwanda and India have already been identified, whilst a UK-based school outreach programme is being developed. If you would like to learn more about LEAF’s work, visit their website – www.theleafcharity.com – or follow them on social media @wearetheleaf.

First trees planted in Pwani University

Global bacterial diversity is 44% greater than previously thought

Bacteria and Archaea, collectively known as prokaryotes, are the oldest forms of life on the planet, they’ve been around for over 3500 million years and are ubiquitous, meaning they are found all across the earth in every environment, some of which are adapted to living in extreme environments such as hot springs, hydrothermal vents and glacial environments.

Although some bacteria cause a variety of diseases in plants and animals, including humans, bacteria and archaea are key for a variety of environmental processes, including aquatic photosynthesis by cyanobacteria and nutrient cycling in terrestrial and aquatic environments. As well as this, some prokaryotes form key partnerships with animals and plants, such as nitrogen fixing species in plant roots and gut bacteria which help break down food.

Some heat loving (thermophilic) bacteria aggregate and form colourful mats at the Yellowstone national park (© S. Scully)

For these reasons, studying bacteria and archaea is particularly important, to understand their use in medicine and combatting disease, their role in the environment and potential to buffer habitat against environmental change, and their importance in biotechnology. Bacteria and archaea are notoriously difficult to study in the lab, as their tiny size and immense diversity in metabolism and optimal requirements make it difficult to culture them. As a result of this, researchers have turned to genome sequencing as a way of studying these organisms.

Collaboration between researchers across the world has led to the ‘Genomes from the Earth’s Microbiomes (GEM) catalogue’, a database which contains over 52, 000 draft genomes, encompassing a large spread of samples collected from all across the world, including agricultural and natural soils, oceanic and freshwater samples, and sample collected from associated human/animal hosts and symbiotes.

Organisms such as these cyanobacteria leave traces of DNA in their environment, which can be detected using metagenomics (© J.Dazley)

The GEM catalogue has been possible despite the difficulty of bacterial culturing due to a revolutionary technique known as metagenomics. Essentially, organisms leave traces of DNA in their environment, such as lakes, soils, etc., which can be picked up in sampling, meaning that growing the species in the lab is not required to study it’s molecular biology. Through this, samples are sequenced and the DNA of various organisms can be detected, which also gives an idea of the biodiversity of the habitat.


The development of the GEM catalogue has provided researchers with an invaluable resource for studying bacteria, from their ecology, molecular genetics to help tackle disease and understand more about their place in the environment. The database has also shown that these microbes are far more diverse and numerous then we once thought, providing a wealth of information for researchers .

North African long billed Pterosaur fed like modern wading birds

A new species of pterosaur about the size of a Turkey has been discovered by UK researchers. About 110 million years old, this strange finding is key to understanding the true diversity of these ancient winged reptiles.


Discovered in Morocco, North Africa, the remains belonged to a small winged reptile, or pterosaur, called Leptostomia bagaaensis which lived during the middle cretaceous period, between 94 and 113 million years ago. The fossil consists of a pair of long, toothless and flattened jaws, which bear resemblance to the beak of a curlew, a type of wading bird common on British coastline.

The long, sensitive beak of Leptostomia would have been used to probe for aquatic prey
(© J. Dazley)

Although it is a common beak shape in birds, it was previously unheard of in pterosaurs, and originally was not thought to belong to a pterosaur at all. When researchers at the universities of Bath and Portsmouth analysed the mandibles, CT scanning revealed a network of internal canals – surface compressions across the surface of the beak – similar to those found in wading birds such as curlews and sand pipers. This made the beak highly sensitive to touch and it is very likely that this pterosaur could use its beak to detect prey.


Despite being a desert environment now, the Kem Kem formation of Morocco, where the specimen was found, would have been a rich habitat in the mid cretaceous period, consisting of rivers and estuaries. So this pterosaur, attracted to the area by the rich source of prey, would likely flock in large numbers, sifting through the water and probing for prey such as aquatic insects.


This is a really exciting find for researchers because it has revealed new feeding behaviours previously unknown in pterosaurs, further unearthing the diversity of these reptiles.

Leptostomia bagaaensis (© M. Jacobs, University of Portsmouth)

Black bees reintroduced at Kingcombe centre, Dorset

Dorset wildlife trust has recently introduced a colony of black bees into the DWT Kingcombe in West Dorset. The aim of this project is to establish a successful regional population in the area and to study foraging habits and pollen preferences in the colony, to better understand these bees’ behavioural patterns. The colony was extracted from an already established and successful colony in South Wales, and introduced to the Kingcombe centre orchard.

The dark European honey bee (Apis mellifera mellifera)
Photo credit – V. White

Also known outside of the UK as the dark European honey bee (Apis mellifera mellifera), the black bee is a subspecies of the European honey bee (A. mellifera). UK populations of the black bee were thought to be extinct by the 19th century, mainly due to a proliferation of tracheal mites, tiny parasites which infect and reproduce in the breathing tubes of the bees, however small isolated populations were found in Wales and Scotland back in 2012.


Considered as the ‘native’ honeybee, the black bee is perfectly adapted to the colder climate of the UK, able to fly and survive in colder temperatures, considerably larger than the continental honeybees, and with longer hairs on the thorax. It is also thought that these bees are more resistant to some diseases, such as bacterial and amoebic infections.


It is hoped that the establishment of this colony will not only help to increase local pollinator diversity, contributing to local ecosystems by boosting pollination, but also prevents an exciting opportunity to understand more about the bees’ behaviour in order to conserve them and increase local biodiversity.