Category Archives: Scientific

Man Orchid Monitoring Saturday 3rd June 10:00am

As reported last week the first flower spike of Man Orchid  has been spotted so we are now planning this year’s survey. With the support we have received for this event historically we are being ambitious this year and plan to survey the whole reserve (well the parts likely to support Man Orchids).

Your assistance with this task would be greatly appreciated but please note some of the survey will require walking up and down some significant slopes. We will try and match transects with people’s capabilities / wishes and of course we do allow you to deviate round very steep slopes and hawthorn bushes!

If you would like to participate in this event then we will be meeting at 10:00am in the main car park off Wittering Road. Weather and enthusiasm permitting we will cover at least compartments one and two (West end of the reserve) but you are welcome to join us when you can and for as long as you want. The area we can cover will be dependent upon how many volunteers we get so feel free to bring family and friends along. There is no charge for this event as it helps with the science.

There will hopefully be some experts present to answer any questions you have and for you to increase your general knowledge of the reserve and its resident species.

I look forward to meeting as many of you as possible on the day. If you can let me know you will be attending by e-mailing records@fbhh.org.uk that will help with the planning.

Plant Monitoring

With the Pasque flowers about at their peak and Cowslips still present in very healthy numbers right across the reserve, we are starting to plan the plant monitoring for 2017. The early purple orchids which have appeared in the last few weeks will soon be joined by Pyramidal Orchids, Fragrant Orchids, Bee Orchids, Frog Orchids, Twayblade, Common spotted Orchid, Spring Sedge and Knapweed Broomrape all of which have been recorded and monitored during the past 40 years. To maintain this database help is required, so please if you are interested in participating in any of these surveys do let us have your contact details. E-mail records@fbhh.org.uk and we will let you know how you can help.

F.B.H.H. Database

Work over the winter has seen many of the historic records of surveys of the reserve added to the F.B.H.H. database. The records are of somewhat varying age and detail but in general they give a comprehensive record of what has been seen and when on the reserve.

Currently, and allowing for some duplication due to species name changes and re -classifications, errors in recording  and simple transcription errors the database contains the following information

Flora – 363 entries

Lichen – 57 entries

Mosses – 71 entries

Fungi – 77 entries

Moths – 104 entries

Butterflies – 36 entries

Molluscs – 31 entries

Spiders – 10 entries

Myripoda – 5 entries

Other insects – 390 entries

Birds – 111 entries

Mammals and Reptiles etc..  – 6 entries (not including humans, dogs or cats!)

So there is plenty to look out for and please do let us know preferably with a photograph attached of anything unusual you see on the reserve so we can add it on to the database.

Also we would welcome hearing from anyone carrying out a survey or maintaining a list of what they see during 2017 so we can update the records with current sighting dates. (Current database indicates Turkey Oak has not been seen on the reserve since 2014 perhaps a slight oversight  they are not that difficult to spot!!!)

First signs of Spring?

With the meteorological beginning of spring only 5 days away it is worth looking out for those first signs of spring around the reserve. The violets should soon be showing their brave colours closely followed by the first cowslip buds. The start of the butterfly transects is only just over a week away. This is officially designated as week minus 3 showing the effect of climate change on the timing of natures events since the transects started being recorded.

This all seems a little distant today with storm Doris battering the reserve with such ferocity that even my chocolate Labrador was questioning why were out walking this lunch time. Perhaps optimistically I did note that the two flocks of Fieldfares, I spotted in the fields to the east of the village, were heading north. Maybe a sign of warmer weather or perhaps just the only option given the strength of the wind!

Please do let me know via records@fbhh.org.uk when you first see particular plants, butterflies, invertebrates and migratory birds on the reserve. That will help me keep other visitors to the site advised on what there is to see during their visits.

I am hoping to complete the update to the reserve database very soon. Adding all the information uncovered during the winter searches of the archives and the 2016 site visit records provided to me. Target is to finish this before the temptation to be out and about becomes too strong. So please look out for an update on the contents of the database in the next month.

Mid-July on the reserve and some historic notes

At least some dry weather has arrived and the flowers are doing there best to put on a fine display even if the grass and vegetation is rather lush following the consistent rainfalls throughout spring and early summer. One slight benefit has been probably the latest record of a Pasque flower in bloom during a visit by a Warwick Natural History group to the reserve on 12th July.  I would be interesting to hear (records@fbhh.org.uk) of any later recorded dates from previous years? The warmer drier weather has also brought out the butterflies in reasonable numbers with Meadow Browns, Ringlets and Marbled Whites vying for the top spot on the transect walks. The latest walk added Gatekeeper, Comma and Green-veined white to this years records. Look out for the Chalkhill Blues (pictured above) that are expected to be flying in the next week or so.

With the general floral display probably at its peek now is a good time to visit the reserve and brush up on your flora identification but also keep a look out for Grass snakes (Tim has recently seen a large specimen on site).

I also promised earlier in the year some extracts from the historic Summer Warden reports so here is a taster from 1977 just one year after the site being declared a National Nature Reserve.

“The grassland belongs to the Tor-grass Brachypodium pinnatum Upright Brome Zerna erecta type and contains the whole range of species characteristic of this association. The Man Orchid Aceras anthropophorum is locally abundant and several other orchids are present. The Pasque Flower Anemone pulsatilla occurs frequently and this reserve is one of its main strongholds. The Mountain Everlasting Antennaria dioica is primarily a northern species and is represented on the Hills and Holes by one small patch in the Northants Naturalists area. (Note added: Now designated compartment 1 – South west quarter). This area has the most varied flora which must be partly due to scrub clearance carried out by Trust volunteers.

The last sentance remains true today – (more or less forty years on) and just shows how long term any management strategy needs to be. Perhaps in another forty years the clearance in circa 1999 of the turkey oak trees and scrapping back to bear limestone waste in compartment 4 (South-east quarter) adjacent to the wooded area will show the same benefits. The survey data also shows how management of the reserve (probably consistent annual sheep grazing) has led to a dramatic reduction in the amount of Tor Grass on the reserve with  72% of quadrats surveyed found to containing it in 1978 compared to only 16% in 1996.

Weather Report from the Reserve

Well the last week has certainly seen spring finish and summer begin with a strong reminder of winter and autumn. Everything feels like it is a few weeks behind this year so I thought I would look at the weather records to see how this spring compares to previous years. Thanks to the nearby location of Wittering Airbase we have reasonably indicative data for the reserve for the past 20 years.

This graph shows the average daily temperatures for the months March to May (meteorological spring). The boxes and lines show the spread of daily average temperatures and the heavy line joins up the averages for each spring.

Average Daily Spring Temperatures

So whilst not the coldest spring, 2013 still holds that record by some way, it has certainly been colder than most. Perhaps a look at the temperatures for the winter just passed (December 2015 to February 2016) gives a clue as to why we think this has been so cold!

Average Daily Winter Temperatures

Here we clearly see it was the mildest winter in 20 years and for the third year running the average temperature for any day very rarely dropped below freezing. A fact that is evident from the devastation the slugs and snails are causing in my garden!!

Whilst on the topic I thought for a bit of fun and for those planning a visit to the reserve I would identify the statistically warmest day to visit and for those planning ahead the warmest week (on average). So based on the average daily temperature over 20 years Thursday’s appear to be the warmest day to visit whilst Tuesday on average almost 0.2 degrees colder might be worth avoiding. Not surprisingly the warmest average week is at the beginning of August so a visit on 4th August this year should see you “basking in sunshine” if the statistics are to be believed!!!!!!

 

Man Orchid Count (Interim Report)

© Petersrockypics
© Petersrockypics

A big thank you to all those who turned out last Saturday 30th May to look for small green flowers in the green grass! Despite the challenge and with the help of good weather the totals so far for this year are as follows:

Compartment 1 (SW) – 251 (161 for this compartment last year)

Compartment 2 (NW) – 292

Compartment 3 (NE) – still to be surveyed

Compartment 4 (SE) – 79

Compartment 6 (N) – 1

NB Compartment 5 is the designation for the road side verge

Total to date : 623 (Estimate circa 650+ once compartment 3 completed)

This compares to 184-2013 and 1,027 – 1998 the latest two comparable whole site surveys. We wait to see if the fixed plot surveys support these encouraging signs of an increased population after many years of low numbers.  Fixed point  Man Orchid count data from 1997 to 2014.

The Big Spring Watch

With the first Pasque Flower of the season seen on the reserve during my visit on Tuesday this week spring is well on its way. For those who saw “Springwatch at Easter” on BBC the reserve provides an opportunity to participate in their survey as all five signs of spring can be seen on the reserve. Please feel free to e-mail me at records@fbhh.org.uk with your sightings on the reserve of the English Oak coming into leaf, Hawthorn in flower, seven spot ladybirds, Orange tip butterflies and of course the arrival of the first Swallow. See www.naturescalendar.org.uk for more national information.

The Red List

How special is the flora of Barnack Hills and Holes National Nature Reserve?

The Holy Grail for a botanist is a red listed plant. Finding one is very satisfying, and it doesn’t often happen. So what are Red Lists and what is their relevance to Barnack Hills and Holes?

Red Lists are lists of plants or animals that are in danger of extinction in a particular area or country. There is a standard scientific method for selecting these species, laid down by the International Union for the Conservation of Nature. Assessments are based on specified thresholds of population reduction, decreasing geographical range and small population size. A plant may be widespread, but if it is being lost from many of its sites it may qualify for red listing. There are three categories of threat: Critically Endangered, Endangered and Vulnerable, which are allotted to species according to the degree of danger that they face. The term Near Threatened is applied to species that are close to qualifying for a Red List. Species that cannot be classified because of insufficient information are Data Deficient. Least Concern is the term used for the rest of the species, which are regarded as currently safe from the threat of extinction.

DSC01798-1We have two national Red Lists of flowering plants and ferns that are applicable to the Barnack area. One is the British Red List, which was originally produced in 1977 and is revised regularly by the statutory conservation bodies, including Natural England. The other is the Red List for England, first published in September 2014 by the Botanical Society of Britain and Ireland. As might be expected, the two lists are not identical because they are based on different geographical perspectives. A plant that is common in Scotland is unlikely to qualify for the British Red List, but that same species may be included in the Red List for England because it is rarer and more threatened in southerly, lowland situations.

The following table gives the nationally red listed and Near Threatened flowering plants that currently occur at Barnack Hills and Holes. Seven species are on both British and English Red Lists and an eighth – Mountain Everlasting – is only on the Red List for England, being an example of a plant with a predominantly upland distribution. A further four species are Near Threatened in England, whereas in Britain as a whole they are classified as Least Concern.

Natural England and the Friends of Barnack Hills and Holes are very keen to gather further information about the plants growing on this ancient limestone quarry site. Records, including the date and details of the recorder, can be submitted to records@fbhh.org.uk.

The occurrence of eight nationally red listed plants in an area of only about 20 hectares is very unusual. This, and the presence of one of the strongest populations of Pasque Flower in the country, indicate that the flora of Barnack Hills and Holes is outstanding. Its status as a Site of Special Scientific Interest and a National Nature Reserve is fully justified and it is vital that the site is managed for the benefit of its threatened grassland flora. To be able to find six red listed plants during a single visit in summer is extraordinary: there are very few places in Britain where this is possible.
Margaret Palmer
4th October 2014

red list

This table can be opened in a separate window or downloaded as a pdf file – click here

Bank Holiday Weather

The traditional bank holiday weather has me thinking about this years fine display of butterflies and flowers on the Hills and Holes. At least my perception is the flowers were more prolific than usual and the butterflies earlier and more numerous. Perhaps the mild winter had made a contribution but was it that unusual? So I have “dug out” from the internet the weather records from Wittering (only a mile or so from the reserve as the crow flies) and discovered that since the accessible records began in July 1996 it had been one of the mildest winters (along with 2007).

winter box

 

Particularly unique and perhaps significant for the over wintering insects there was no single day when the average temperature recorded was below 0 degrees celsius.

winter plot

Spring has also been one of the warmest, again notable for its absence of any really cold days.

spring graph

It will be interesting to see if the results of the butterfly and other surveys support my ad hoc observations and if we really have seen  the benefits of a mild winter and warm spring last through the summer. For the information of those who took part in a very wet Man Orchid count it could have been worse. The rain fall on the 24th May (10.92mm) was only the fourth heaviest of the year (perhaps made to feel worse by the19.05mm that fell on 22nd May but not as bad as the 23.88mm on 10th August. With the 12.95mm that came down on 20th July these are the only four days so far this year to have reached double figures local to the reserve. Now I have the data please let me know if you have any specific questions on the historic weather.