~ Lemon Discos ~

As part of the Biodiversity module, we went on a Fungal Foray around campus. One species I found particularly interesting was Bisporella citrine or Lemon Discos. I went back the following day to take some close-up photographs of them and then did a small amount of research.

Each elliptical shaped fungus is extremely small (around 2mm in diameter) but they occur in clusters on decaying wood in autumn. Interestingly, it is an extremely widespread species, being found in 6 continents!

~Winterton Dunes - Trip Report ~

During this trip to Winterton Dunes, we undertook tasks:

Transect

We ran a transect from the seashore, through the dune systems to see the changes from foredunes to mature dunes. This was done using quadrats, where we recorded the following:

• Number of plant species
• Tallest vegetation height (cm)
• % Cover of sand
• any other notes (droppings, disturbance etc.)

The raw data is shown below

Of particular interest was the change in plant diversity across the transect. 

Between 0 and 200m there is an obvious positive correlation: as you move further from the sea, plant diversity increases. This is possibly due to the reducing hostility of the environment, with greater protection from wind and a reduced risk of salt water inundation.

After 200m however, plant diversity decreases slightly (though plateaus almost immediately). There are a number of possible explanations for this. Increased grazing activity by rabbits and sheep was noticed on the landward side of the dunes, with the more mature dunes providing the necessary stability for rabbit warrens perhaps. Alternatively (though likely a combination of different factors), the varying topography of the dunes could have had an impact. 

Disturbance impact on lichen

For this we used systematically placed quadrants at fixed distances from the footpath in order to measure any difference in lichen cover at different distances from the path. If Lichen cover decreased closer to the path, this could indicate that disturbance from visitors using the footpath is having an impact. The results are shown below:

 These results do suggest a positive correlation between distance from the path (thus less disturbance) and the mean % cover of lichen.

Given more time, it would have been good to cover more than 6 sections of footpath. Ideally, a number of the footpaths criss-crossing the site could be investigated and perhaps cross-referenced with the amount of disturbance (footfall) each of these paths gets. 

Given the task of increasing lichen distribution, I would be inclined to rope areas with particularly low lichen density (but with potential for high density) to reduce impact. I would also introduce signs both to educate people about the importance of lichen for the NNR (and how this status prevents it from becoming a golf course etc.) along with notices to request that dogs are kept on leads (this will provide further protection for ground-nesting birds that use the dunes).

~ Bure Marshes - Trip Report ~

A very enjoyable walk around this largely private NNR, guided by the extremely knowledgable Rick Southward, below I have listed some of my favourite moments and things of interest from our visit:

• Rick showed us a Water Solider (Stratiotes aloides), a freely floating aquatic plant that favours the  dykes of the fens, it was really interesting to learn of the ecological role this plant has in adding structure to the water and providing shelter for aquatic invertebrates such as the larval form of Norfolk Hawker (which favours, but is not dependant on the plant) from fish predation.
• Rick also mentioned that all the plants in the UK were one gender, and having researched this, it would appear they are all female (with only a couple of male records, likely to be escapes from garden ponds etc.)!



• Current research suggests that the new leaves that grow in spring contain air pockets allowing the plant to float. As the older leaves die back in autumn they become waterlogged which causes the plant to sink again.

• I also enjoyed learning about the management techniques employed in managing the fens, as well as seeing this ecosystem service first hand.
• In order to disrupt succession and cut costs, cattle are used for grazing
• grazing a natural management technique as it mimics the herds of large herbivores Britain will have once had
• Marsh orchids for example grow on grass verges on edge of reeds and marshes
• grazing also adds to topography, again increasing microhabitats and can offer invertebrates protection from high water levels
• increases light levels to surface, allowing plants such as Marsh pennywort to grow

There are so many other things to mention including the problems from nitrates in agricultural run-off, and the management of the wet alder woodland, but I don't want the post to drag on too long!

~ Willow Emerald ~

Willow Emerald - Chalcolestes viridis


A large, metallic, olive-green damselfly that - like the other emerald species- has the unusual trait among damselflies of perching with it's wings half open. It often rests quite high up on trees (especially willow) that overhang slow-flowing rivers. As such, the abundance of willows overhanging the River Yare at UEA provides abundant habitat for this species. 
Interestingly, this species is a very recent colonist to the UK, and still considered very scarce in the UK as a whole. It was first recorded in the UK in 2007 and has since spread well across East Anglia. New sites are being found each year, and so it seems likely this species will continue to spread further west.

Mating Willow Emeralds

Unlike other damselfly species that lay their eggs in water, this species lays their eggs in the branches of trees that overhang water. The eggs stay in the branches until next spring when they hatch and the prolarva then fall into the water where they rapidly grow and in a space of a few months, emerge as adults.

Identification is relatively straight forward as there is little overlap between this species of emerald and others. To conclusively ID however, look on the side of the thorax for a prominent spur (shown below). The cream/pale-brown pterostigma (the coloured section on the outer edge of the wing) is also a good feature look out for. They are a late species to emerge (usually around mid-late August) and can be found right until the end of October (even into the first week of November if conditions are right), so there is still plenty of time to go and search for them.

Characteristic 'spur' marking on thorax

They appear fairly widespread at UEA, though hotspots seem to be in the trees/hedges along the western edge of the broad, and along the stretch of river that runs to the south of the broad, up until the boardwalk at the eastern end.