Biodome carnivorous plants reveal hidden microbial diversity

Some carnivorous plants hold ‘pools’ within the plant consisting of rainwater and secreted substances such as sugars, used to lure and trap insect prey. Microscopic analysis of this fluid collected from pitcher plants (Sarracenia sp.) and bromeliads (Brocchinia sp.) growing in BU’s Biodome has revealed a rich diversity of single-celled microorganisms. These microbes, less than half a millimetre in length, are known as ciliates and distinguished by hair-like cilia that they use for locomotion and feeding.

Ciliates are incredibly important grazers, feeding on bacteria, algae and organic matter, and are a crucial part of the microecosystem within the bromeliad and pitcher plant pools, which also includes algae, bacteria and insect larvae, such as mosquitoes. In turn, they are also fed upon by mosquito larvae and copepods that also grow in such pools, playing an important role in energy transfer from microbes to animals.

One of the microbes found within the pools was the ciliate Euplotes, pictured above. © J.Dazley
Exploring Plankton Diversity in Southampton Water

Exploring Plankton Diversity in Southampton Water

Undergraduate students in the department of Life and Environmental Sciences investigated the diversity of phytoplankton and zooplankton in Southampton water as part of their third-year Biological Oceanography module. Using the research vessel RV Callista at the National Oceanography Centre Southampton (NOCS), samples were collected at 5 locations, or “stations”, between Calshott and the Itchen River.

Environmental data was collected at each station using an array of sensors, measuring parameters such as temperature, salinity, chlorophyll and oxygen concentration. Phytoplankton were collected at two depths at each site, representing deep and shallow water. Zooplankton was caught using a plankton net, with a 120µm mesh to catch zooplankton in the net. These samples were subsequently analysed back at the university.

Trawls and grab samples were also used to investigate the benthic (bottom dwelling) communities living on the seabed and to analyse the oxygen content of the sediment. Benthic animals found included starfish, fish such as gobies and flounders, cuttlefish, crabs and ‘moss animals’ (bryozoans).

Back at BU, the phyto- and zooplankton samples were analysed using microscopy. A variety of diatoms and dinoflagellates were found in the phytoplankton samples, and barnacle larvae, copepods and the larvae of marine worms were found in the zooplankton samples. Microbes too small to be seen under the microscope were counted using flow cytometry, a technique used to identify cyanobacteria and other minute cells.

The study demonstrated the great diversity of planktonic and benthic life in Southampton water, and highlighted the importance of monitoring and understanding the microscopic life of the sea since the microscopic life , as the base of the food web, is crucial in sustaining the larger and better understood forms of marine life.

Saving Europe’s Crickets and Grasshoppers From Extinction

A recent assessment of cricket and grasshopper species in Europe has shown that up to 25% are facing extinction. According to the International Union for Conservation of Nature (IUCN), the group Orthoptera, which includes Grasshoppers, Crickets and Bush Crickets, is the most threatened group assessed so far. An estimated 1000 species of Crickets and Grasshoppers are found in Europe. They play a vital role in grassland ecosystems; many species of birds and reptiles feed on them. The main factor contributing to decline is habitat loss due to wildfires, tourism and intensive farming. Many species are confined to small areas due to the break up of their natural habitats; for example the Crau Plain Grasshopper has been confined to the steppes on Southern France.

So what can be done in order to protect these insects? According to research from the IUCN Global Species Programme, more effort must be put into restoring the habitats of these insects in order to increase population size. This can be achieved using sustainable grassland management by employing traditional agricultural practices. It is imperative that these insects are saved from extinction, not only because they are very important biodiversity indicators, but also they are an integral part of grassland ecosystems.

Image Credit: Axel Hochkirch

Bittern Numbers Booming In The UK

The Common Bittern, Botaurus stellaris, a shy, secretive relative of the heron, was once extinct in the UK, however the bird has made a massive comeback over the years. Bittern numbers are now at their highest recorded numbers in the UK.

The bittern lives mostly in reed beds and is rarely seen due to the superbly camouflaged streaked plumage, which blends perfectly with the environment. However, the male’s booming call can be used to identify the presence of bitterns, and so researchers have been able to count these birds.

This year, the breeding population has been at it’s highest since the 1800s, with 140 singing males seen, compared to 11 in 1997. Somerset has the largest bittern population, with 20 males located at Ham Wall nature reserve,

According to the RSPB, one factor contributing to UK population increase in bitterns is due to restoration of quarries, which has helped bitterns to thrive. The bittern is still on the RSPB’s red list, but the development of these restored quarries is expected to increase the UK’S bittern population in the future.

Image credit: Helen Briggs

Restoration of Native Flora Encourages Bird and Insect Pollinators

Scientists investigating the effect of exotic plant species on native plant biodiversity on the island of Mahe in the Seychelles have found that ecosystem restoration by removal of exotic plant species is linked to an increase number of pollinating species such as bees, butterflies and birds and an increase in flowering of native flora.

Eight study sites on Mahe’s mountains were monitored for a period of eight months, with non-native plant species being removed from four sites. Native plant species were found to be flowering more frequently and attracting more pollinators. An increase in the number of pollinator species was also observed 6-12 months after the removal of exotic species, including bees, wasps, flies, beetles, moths, birds and lizards.

The research from Mahe mountaintops gives us a clear demonstration of the role of ecosystem restoration in pollination and interaction between plants and animals, and that ecosystem degradation is, at least partially, a reversible process.

Picture credit: C. KAISER-BUNBURY