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.

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

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)

Fungi and other soil organisms are key in preserving biodiversity

Fungi are often seen as fruiting bodies, or toadstools (© Camila Duarte)

Largely invisible and often overseen, fungi and other microscopic organisms are highly abundant in soils across the world, and play a fundamental in maintaining the biodiversity and nutrient balances in their ecosystem.

Fungi, although visible in the form of fruiting bodies, or toadstools, during certain times, are largely invisible, existing as microbial threads in the soil. It is estimated that there are some 3.8 million species of fungi, only a fraction of which have been formally described and identified. These organisms are incredibly abundant in soils around the world, an are a key component of biological nutrient cycling, as they break down organic matter, releasing key nutrients and compounds from dead bodies. Fungi are found in a variety of areas such as rainforest, woodland, grasslands and even rocky substrates (in the form of lichens) but are most abundant in open areas such as grasslands and Savannah, where they are important in helping poorer soil uptake nutrients.

Fungi exist mainly as a bundle of microbial threads called a mycelium (© Nigel Cattlin)

In the Amazon rainforest for example, fungi are surprisingly abundant and varied. For example, a teaspoon of rainforest soil is estimated to contain around 1800 species of microscopic organisms (according to a study carried out by Dr Camila Duarte of Germany), at least 400 of which are fungi. These fungi are so diverse and they occupy a variety of niches in the forest, such as lichen (a symbiotic relationship between fungi and microscopic plants), some living commensally in the roots of plants and some as plant pathogens and parasites. Each and every one of these plays a significant role on the forest floor, breaking down organic matter and releasing nutrients back into the soil, to be used by plants and animals.

In this sense, the sheer diversity of fungi in the soil means that it is essential to consider this hidden diversity in conservation efforts, particularly in such fragile ecosystems as the Amazon rainforests. Due to their inconspicuous nature fungi are often overlooked in biological surveys, but they are key for nutrient cycling and also act as carbon sinks, absorbing carbon dioxide from dead organisms.

An abundance of fungal species are found in the soils of the Amazon rainforest (© Nathalia Segato)


Some species are also edible, and are a source of medicine, indeed fungal compounds are being considered as new antibiotic sources in the light of antibiotic resistance. On the other hand, some fungi are considerable pests to crops, while others are disease-causing pathogens which cause disease in humans and animals. There is much to learn about soil fungal diversity, in order to incorporate these organisms into conservation efforts, and to help maintain biodiversity.

Isle of Wight Pterosaur fossil hailed as UK first

A fossil recently discovered on the Isle of Wight has been revealed as a first of its kind to be found in the UK. The fossil belonged to an ancient flying reptile which would have soared through the skies of southern England 100 million years ago.


The fossilised jaw fragment was found by an amateur fossil hunter on Sandown beach, Isle of Wight. The delicate fossil was identified as a tapejarid (a type of medium-sized crested pterosaur) by scientists at the university of Portsmouth, recognisable by the characteristic shape of the jaw and minute holes in the jaw, which experts think were used to detect prey. The fossil has been donated to the IoW dinosaur museum for future display.

The fossilised jawbone of this animal was discovered on Sandown beach, IoW (credit: Portsmouth University)

So, what did this animal look like? These pterosaurs were small to medium sized and lived around 100 million years ago, during the cretaceous period. With more curved wings than other species, they are well known for the large bony crests on their heads. It is very likely that these crests would have been highly colourful in real life, almost twice the size of the skull, and probably used to communicate and attract partners, much like many bird species such as pheasants and birds of paradise. There has been much debate concerning the diet of these animals, but it is thought that they fed on plant material, especially considering that flowering plants were diversifying around the time these creatures appeared.

The crest of Tapejarids was likely very colourful and used in courtship (credit: national geographic society)

The fossil is a key finding for our understanding of these creatures; before the discovery of this specimen, the tapejarids were only known from Brazil, Morocco and China, and this find not only demonstrates a very wide distribution of these pterosaurs, but also showcases the diversity of mesozoic species on the island and surrounding area.

Study reveals tropical rainforests covered much of Antarctica 90 million years ago, during time of the Dinosaurs

Study reveals tropical rainforests covered much of Antarctica 90 million years ago, during time of the Dinosaurs

Antarctica is arguably one of the most barren, extreme environments on the planet, with only one permanent terrestrial resident – the Emperor penguin. However, wind the clock back 90 million years, and the continent was far from a frozen wasteland. New evidence has suggested that this icy continent was largely covered in tropical swamp forest, during the time of the Dinosaurs.


The cretaceous period, which spanned from approximately 145 to 66 million years ago, was a very warm period in earth’s history, with an almost worldwide greenhouse climate, and an abundance of vegetation and tropical forests. Antarctica at this time was mostly covered in a swampy, tropical forest and there were no glaciers at the south pole.

An artist’s impression of the ancient swamp forests of Antarctica (© James McKay)


Scientists at the Alfred Wegener institute, Germany, made this discovery by analysing sediment cores drilled from the seafloor in West Antarctica. These cores show a glimpse of the past environment in Antarctica, with sediments nearer to the bottom of the core representing older geological time. At three metres down on the core, representing the late cretaceous period, the sediment composition changed drastically, composed mainly of a coal-like material, soil, roots and pollen. The team identified over 65 types of plant material, indicating the presence of an ancient conifer forest.

The ancient Antarctic forests would have been dominated by cycad plants such as this one (© J. Dazley)


So, what exactly lived in these forests? The forests would have likely been very similar in plant structure to some of the forests in modern-day New Zealand, dominated by towering tree ferns, cycads and coniferous trees. At this time in history, flowering plants had only recently evolved so were likely rare in these forests. Biogeochemical evidence from the sediment cores also revealed that microscopic photosynthetic life such as algae and cyanobacteria were common in warm lakes and rivers.

Australovenator was one of several carnivorous dinosaurs to roam prehistoric Antarctica (© L. Xing)


These forests were dominated by a variety of dinosaur species, which filled many of the ecological roles of forest ecosystems today. There were giant herbivorous dinosaurs such as the long necked Austrosaurus, and Muttaburrasaurus, a close relative of the Iguanadon, whose remains are commonly found on the Isle of Wight. There were also carnivorous dinosaurs such as Cryolophosaurus and Australovenator, and the tiny herbivorous Leaellynasaura, which likely lived in small groups in the forest. Primitive mammals shared the forests with the dinosaurs; they were furry, egg laying species which were likely similar to modern echidnas and platypus. It is also known that the river networks around these forests were home to a giant salamander-like amphibian called Koolasuchus, belonging to an ancient lineage of animals over 250 million years old.

The giant amphibian Koolasuchus was one of the last surviving of it’s kind, and probably fed on smaller dinosaurs (© BBC)


The discovery of these polar forests is not only an exciting advance for palaeontology, but also shows us how key carbon dioxide levels are in the shaping of an environment. It is known that the tropical climate during the cretaceous period could have only been possible if carbon dioxide levels were much higher than today, so this discovery could give an insight into the future environmental implications of increased carbon dioxide levels in the near future.

Great Hammerhead Shark

It’s #MarineMonday and we would like you to meet our marine friend.

“Colour me in so I can swim!

Hello! I am a Great Hammerhead Shark! Many people are afraid of me and my other friend species, but did you know you are more likely to injure yourself taking a selfie that being around me? I am the largest of all the other hammerhead species! I hace some questions for you:

  1. Where do I live?
  2. What do I eat?
  3. How long can I grow up to?”

Tarsier

Today is #TerrestrialTuesday! Terrestrial simply means anything that lives on land, so today we would like you to meet our tree friend.

“Colour me in so I can climb!

Happy Tuesday everyone! I am a Tarsier and I am a primate. I got my name from the very long bones in my feet! I have HUGE eyes, perfect for my nocturnal lifestyle, which means I am only awake when it is dark outside. I only live in trees; it is very comfy for me! Some questions for you:


1. Which country do I live in?
2. What do I eat?
3. How big am I when I am fully grown?”

#homeschool#homeschoollife#education#homeschooling#onlineeducation#teaching#school#mondaymorning#teachingfromhome#stayathome#wildlifecraftclub

Axolotl

It’s #MarineMonday and we would like to introduce you to our marine friend.

“Colour me in so I can swim!

Hello! I’m an #Axolotl. There’s aren’t many of me left in the wild. I don’t really like water pollution where I live. I just love to swim and I’m very well adapted. I have a very cool skill: I can’t regrow my own limbs! I have some questions for you to find out…

•🏡 Where do I live?
• 🍽 What do I eat?
•💚 How can you help me and my friends?

As a bonus question, see if you can find pictures of what my babies look like!”

Answers will be revealed on Saturday!

#homeschool #homeschoollife #education #homeschooling #onlineeducation #teaching #school #mondaymorning #teachingfromhome #stayathome