Start of Pond Surveying Season

In previous years I have monitored a few ponds in my local nature reserves. This year, I have been more ambitious and have extended both the number of sites to be covered and the scope of the surveys. As I am also wanting to gain experience and work towards my Great Crested Newt licence, I put a request out via my local ARG group to see if anyone would like to help me and have had an overwhelming response, with more than fifteen people coming forward. This means that I will always have someone with me when I go out surveying, which not only makes it more enjoyable but is also safer and I can do more night visits with confidence. The people helping me have a range of experience - some already hold a licence and others are wanting to learn more, so it's great that we can all support each other.

I have arranged to survey all three sites on alternate weeks.  This week was the first visit and was carried out during the day. The aim was to reconnoitre the site and gather environmental data, as well as doing a visual search of the ponds for signs of amphibians but mostly for frog spawn.

The environmental data provides an impression of the health of the pond, but also enables a Habitat Suitability Index to be generated. This provides a score that evaluates the suitability of the pond for Great Crested Newts based on ten factors. Being able to assess this is a requirement of the CIEEM competencies and the GCN licence, so I am trying to get as much experience as possible.  I have also been compiling the results into a summary document for each site to gain experience of producing ecological reports.

Our first visit was on Saturday to Letchmire Pastures. It took slightly longer than I envisaged to carry out the survey, but once I re-familiarise myself with the paperwork I am sure this will become easier. We found some frog spawn and stickleback in one pond, but not much else of interest.

On Tuesday, we surveyed Ledston Luck nature reserve. This was a much more interesting visit. Whilst looking for frog spawn, I stumbled across a feeding pile and latrine and confirmed water vole presence on the site. This was really exciting and totally unexpected and it made my day. We also saw signs of other mammals including fox, deer and field vole. There are two really nice ponds on site, two that are not so good as they are in very wooded areas, and some scrapes on the plateau that are unlikely to support amphibians.

On Thursday, we visited the largest site at Rothwell Country Park. I am more familiar with this site, as it's the one I have surveyed the most of the years. Although we did find frog spawn, there were no signs of newts although the water was very turbid in most of the ponds. I am not sure what is causing this as there has not been much rain recently.

On all of the surveys, we did a brief invertebrate sweep to assess the water quality. I do enjoy this part of the survey, and I would like to be able to identify more of the species, though I am getting more familiar with them already.

The most time-consuming part of the week has been compiling the results. I am transposing these onto my own spreadsheet, but they also have to be keyed onto the PondNet website.  I ultimately want to produce a report for each site, but am still experimenting with this and am researching what I should include and how this is best presented.

On Friday, I carried out an extra survey and went to Skelton Grange Environment Centre. As these are not part of my PondNet project, I carried out a shorter survey and just compiled the HSI scores for the ponds. This has given me good practice at writing up the results and thinking about their implications.

Tadpoles Developing

The last few weeks have been rather busy and a little bit stressful.  Several days elapsed until additional spawn was laid, and whilst I was waiting I was starting to panic that I wouldn't be able to complete my experiment. Since then, I have had over a dozen clumps of spawn. It has been a little difficult to catch this quickly once it has been laid, as the frogs tend to lay new spawn on top of existing spawn so that it forms a mat. I actually now have four replicates of the experiment running: all of the first batch (Replicate A) seems to have spoiled so I took a further batch (Replicate D) to ensure I had three sets of results to compare.

Another stressful moment was when my pH meter failed: I discovered that water had got into the battery compartment and fried the electrics. I ordered another on overnight delivery, and although it was much more expensive it seems a lot slower and only produces readings to 0.1 decimal place. I have taken to checking it against the calibration fluid before I start checking my water treatments as I am not overly confident in the new meter so am erring on the side of caution.

Now that I am over a week into the experiment and have three replicates running I am starting to get some good results. It was impossible to identify the early stages of development without a microscope, but once the embryo started to develop a tail bud I could allocate it to the appropriate Gosner stage.  Development seems to be progressing very quickly, with just a day or two between the tail bud first developing and the gills forming. The embryos are now moving, mostly curling and uncurling, within the central egg sack. The next stage to look for is a heart beat behind the gills, but I am not sure I would be able to see this without a microscope.

Although none of the embryos have hatched yet, there are some obvious developments. The least acidic treatment, at 5.5 pH, seems unaffected and is developing in line with my control group which is in neutral pond water.  The tadpoles in moderately acidic water of 4.5 pH seem to be about a day behind in development terms, and there are slightly more deformities/undeveloped eggs.

The most acidic treatment, at 3.5 pH, is much different - none of the eggs are developing. The inner sack has turned opaque and the eggs generally are cloudier and more condensed. In some of them, the nucleus seems to have broken apart. I am continuing to monitor them, but doubt any will hatch.

I have taken lots of photos and notes to remind me of each development stage, and this should make it easier when I come to write the discussion section of my dissertation.

Tadpole Experiments

As I'm close to completing my degree, in February I started my dissertation project, a 30-credit final year module on environmental science. I get to choose my own project, as long as it compares biotic and abiotic factors. I have chosen to study common frog tadpole hatching success at different levels of water acidity. This follows on from my second year project where I did some fieldwork in a local nature reserve, and found that amphibians were absent from one particularly acidic pond. After some literature research, I have set up a home experiments to assess at what point acidity is lethal, and at which point it can develop into frog spawn. Is there a tipping points or a gradient along which acid impacts development?  The last few weeks have been quite intense in planning and setting up the experiment.  I had to get approval from the module team early, as the deadline for my first assignment isn't for another ten days, but the frogs arrived in my pond in mid-February.  I am at a slight disadvantage as I am having to cram a lot of work up front, but it will mean that my data collection is over relatively quickly and I have the summer to write up and get involved in other conservation tasks.

Yesterday, activity in the pond increased and the first clump of spawn was laid. This happened at lunchtime, just as I was about to set off for an overnight trip. As I had committed to collect spawn within 24 hours of it being laid, needless to say my trip was delayed while I collected the spawn and decanted it into separate tanks.

First I split the clump of frog spawn into four different batches.  This was much harder than I imagined as the jelly stuck the eggs together very firmly. Three smaller clumps were put into my least acidic water to acclimitise, then two of the clumps were gradually moved to more acidic water.  One of the four clumps was returned to the pond.

The experiment has only been running a day and so it's not really possible to see if there is a difference between the spawn in the different water treatments.  The one in the most acidic water does look slightly more cloudy, but this could be my imagination. There are a couple of deformed eggs, but these occur in different treatments so it is not necessarily the acid that has caused it - it could have been damaged whilst I was splitting the spawn.

Hopefully the frogs will produce more spawn in the coming days as I need to carry out at least three replicates of the experiment. I am trying to photograph the spawn at different stages so hopefully there will be some interesting photos posted here over the coming weeks.

Coppicing Tasks

Unfortunately I missed a coppicing training day organised by the YWT Lower Aire Valley volunteers and Leeds Coppicers, but I still got the chance to practice some skills on the follow-up work days and quickly picked things up from the other group members.

Over the last week I've attended two sessions at Townclose Hills reserve near Kippax.  We started by planting a five new 'standard' trees - a mix of cherry and oak - within the hedge that was laid recently.  These look rather forlorn at the moment, but I'm sure will soon grow and add some interest to the hedge.

We then moved up into the woodland and continued the work that started on the training day. The woodland is being traditionally coppiced to remove scrub and harvest useful wood. This is being done in blocks, so that some areas of the woodland are opened up whilst others are left untouched and continue to grow.

This is a mixed deciduous woodland.  The trees include hazel - which provides a really useful wood products - and sycamore, which is less useful. There were also areas of hawthorn scrub to contend with.

In coppicing, the tree is cut back almost to ground level. The stool that is left will sprout and re-grow in the future, providing a new harvest of wood in around ten years time. Wood that is cut off is then processed into various products. This sorting process can take longer than chopping down the tree.  The photos to the left illustrate the process. Depending on the length, width, flexibility and species of the wood, these could be:

• beanpoles - tall and straight
• fence hurdles - long, flexible and may be slightly bent
• stakes/fence posts - sturdy, straight
• garden canes - shorter, thinner, straight
• firewood - anything else

This was bundled up and will be removed from the site. The remaining brash was collected and laid downslope in three lines of breakers as a sort of dead hedge. This will eventually decompose down but forms an edge to discourage people from walking across the site, and also provides some shelter for wildlife. Robins were already making use of this while we were working.

A couple of pleachers were laid from some of the hazel standards. This is a technique similar to hedge laying, but a branch is cut and laid into bare ground where it should sprout and form a new stool. Following on from the hedge laying course, I managed to do a couple of these on my own.

Today I spent the morning at the Roach Lime Hills reserve. It was a beautiful early Spring morning with views over Leeds.  The group continues to do scrub clearance work on site.  Hawthorn and blackthorn scrub is starting to encroach, so large areas of this are being cut down to restore the area to grassland. Unlike the coppicing, the wood is not good enough to do anything with, so it is burned on site.

Despite the prickly thorns, it was nice to do a task in good weather and enjoy the sunshine.  Leafhoppers were very active as we were enjoying a mid-morning break, and we had a few new volunteers in the group to chat to.

Mapping the South Pennine Grasslands

Through my volunteering at West Yorkshire Ecology, I got the chance to get involved in a short project with them.  They have the task of mapping the Yorkshire side of the South Pennines National Character Area (36) to identify where grasslands are. 

A couple of other volunteers are also involved in the project, as there are several hundred square kilometers to map. On Friday we had a session together, which was really useful as it introduced us to the project and the MapInfo workspace we will be working with.  It was great to have a refresher on MapInfo as I have not used it since I left the Wildlife Trust, and also nice to meet some of the other volunteers as we usually work on different days.

The task is simple: for this first stage of the project, we are digitising part of the 1990 Phase 1 habitat survey that was done across the UK.  This original paper map is currently a flat image and can't be searched, manipulated or modelled.  For the project, we are combining two map 'layers' and creating a new one that can be used interactively.  The first layer is simply a picture of the Phase 1 survey results - on the screen shot below, this shows as the mainly orange-brown colours with notations. The second layer is a more recent, digital version showing the topography and field boundaries.  I have made these lines bright blue so they are easy to see.

The third layer - the one I am creating - is shown in white with the dotted pattern.  This started as a blank canvas, and I have to copy the shape of each field/area from the topography layer, and then annotate the notes - using the information from the underlying Phase 1 map - to show what habitat this shape represents.  You can see in the 'Info Tool' screen that I have created an area of Semi Improved Neutral Grassland, which has habitat code B2.2.

It is fairly easy to do, but the challenge comes when the areas on the topography map don't align to those on the Phase 1 map, or there are different habitat types annotated within one topographic boundary.  Then I get to test my MapInfo skills further by manipulating the shapes or creating new ones to make sure the representation is as accurate as possible.

At the moment, my new map layer is just showing as white where I have digitised the information. Once complete, a theme will be applied to the map. Using the Phase 1 habitat codes, it will automatically colour in the map so that it looks like the underlying picture. However, although it may look very similar once finished, the digitised version will be much more useful as it can be used to gather information about the coverage of each habitat type, and can be used to model different environmental project scenarios.

I'm pleased to be involved as it keeps my mapping skills up-to-date and contributes to a large and interesting project.

Hedge Laying

On Saturday I took part in a work day with the Yorkshire Wildlife Trust's Lower Aire Valley volunteers.  We returned to the site at Townclose Hills, but this time remained at the bottom of the hill to work on the boundary of the nature reserve.  A mixed hedgerow was planted around 15 years ago, and it is now old enough to 'lay' the hedge. This way of managing the hedgerow is good for wildlife as it makes it thicker and promotes new growth.  If livestock were in the field, it would be more secure.  The photo opposite shows a section of hedge that was done last year, with the nature reserve in the background.

We were just a small group of three beginners, which gave us plenty of chance to learn from our expert leaders.  There are many 'styles' of hedge laying.  Ours most closely resembled the Derbyshire style, as the hedgerow was planted in two rows giving quite a thick hedge.  We just practised on one side, and the rest will be finished another day.  Here is my summary of how to lay a hedge.



1.  Prepare the area.  The first tree that you lay is awkward, as it needs a gap to go into. You are basically taking a young tree that is around ten feet tall and upright, and leaning it over on the diagonal.  To make sure it doesn't get caught up on othe trees, you need to prune off any branches coming off the side the tree will be leaning towards (as these would otherwise go into the ground).  We were working from right to left, so the first tree was pruned on the right and leaned to the right. This then creates a gap for the tree on its left to lean into.  You also need to prune off those branches coming out towards you: this will be the face of the hedge and it makes it easier and safer to work.

2.  With a saw, make some horizontal cuts in the base of the tree. These are made at around two inch intervals, starting two inches off the ground. The first cut goes about three quarters of the way through the trunk ... but it is better to be cautious as you can always cut deeper if needed.  On the other hand, if you cut through too far you have killed a fifteen year old tree and will end up with a gap in the hedge!!  The next cut up goes about half way through the tree trunk, and the next one around a quarter of the way through.





3. Gradually thin out the bark.  This is done using either an axe or a bill hook.  Short steady movements are the key. You need a precise result - this is not the same as hacking down a tree with an axe as you need to ensure some living bark is maintained.  It is best to keep the axe angled inwards, pointing at around 5 o'clock (7 o'clock if working the other way).  Once the cut hits the horizontal saw marks, the excess wood chips away and it also stops the axe going down into the base.

4.  Split the base.  When there is about a quarter of the width remaining at the base of the tree, use the axe to gently split the tree vertically downwards, extending the cut face. It is important that this is a clean cut and the living tissue is maintained through the bark and into the roots.  Someone may need to hold the tree to support it and ensure it doesn't bend and break.

5. Bend the tree over. This may need several people.  One person should support the base of the tree. Once filed down, this material should be thin enough to bend. If it is too thick, it is more likely to crack and break.  Other people are needed to support the tree and ease it down into position. Branches tangle on one another and other trees and need easing through.  The tree should end up laying at an angle of around 40 degress. The first in the row may need supporting, but others should support each other.  

 

6. The final stage is to add stakes at approximately two foot intervals. Sawn timber can be used, but we used coppiced branches from the nearby reserve to give a more natural effect.  The pleaches (lain trees) are then woven between the stakes.

The end product can look a little harsh, but as seen from the photo at the top in a few months new growth will start to come through. As the hedge has been pruned, the new growth should be quite vigorous. This task is one that needs to be done in the winter months - besides the fact that it's easier to work with the trees when they are barren, this minimises impact on wildlife and especialy nesting birds.

 

I'm hoping to take part in another session later in the month so that I can get some more hedge laying practice. It was a very enjoyable day and a useful skill to learn.

New Year Planning

After the holiday break, I have had a busy few days organising myself and my studies.  I now have a weekly study planner for the next 6 months or so, which looks pretty scary as I have a lot to keep myself busy.  As ever, my studies are busiest in May-June which is exactly the time when I should be getting out and doing field work - hopefully I will be able to combine both.  I have yet to start my next Open University module, which will be my third year project, but I am hoping to do something great-crested newt related.  This can serve the dual purpose of being a university project and working towards my great-crested newt licence.  I have already started with some research, and have used my Christmas gift money to buy some books and supplies. 

I am attending the ARC UK Herptofauna Workers Meeting in Newcastle in early February, and have also booked onto a Field Studies Council course in April, so should be well set up to start newt surveying in the Spring.

One of my New Year's Resolutions is to continue to improve my plant identification skills.  The first of my MMU modules this year, at the end of May, is on Woodland Plants.  I attended several events in 2014 on woodland plants, so already have quite a good idea about the sorts of plants we will be looking at.  Today I have made a revision list so that each week leading up to the course I will be reviewing a small group of related plants. Hopefully this will prepare me for the course a little better.  I will be doing a lot of newt field work and revising for my OU exam at the same time, so this may take a bit of pressure off.  This week I will be looking at the Violet and Primrose families.

I received some good news today: as I have successfully completed two years of continuing professional development, my membership with the Society of Biology has been upgraded and I am now Kate Wright, AMSB! Another small step in the right direction.