Urban Biodiversity: Successes and Challenges: Epigeal invertebrate abundance and diversity on Yorkshire allotments

2012·3.3 MB·English

by  S Turnbull

Accessed: 2012. Marshall (2009) used a questionnaire-based survey to
NBN Gateway. assess garden and allotment biodiversity and attitudes to 'i
http://data.i'ibn.org.uk/gridMap/grid]V[ap.isp?al]Ds=l it. He found that, among other things, having direct
&srchSpKev=NBNSYS0000005i4. contact with plants and wild animals in a garden or ,
Accessed: 2012. allotment helped foster a wider interest in nature. Thus,
NBN Gateway. allotments, because they typically involve a cross-section
http://data.nbn.org.uk/gridMap/gridMap.isp?allDs=l ofa community, can offer an ideal opportunity to engage
:
&srchSpKev=NHMSYS0000080203. people on an individual or community level and allow
Accessed: 2012. them to take a greater interest in their local wildlife.
NBN Gateway.
http://data.nbn.org.uk/gridMap/gridMap.isp?allDs=l The aims of our research were to test any variation in
&srchSpKev=NBNSYS0000005144. epigeal (ground-dwelling) invertebrate abundance and I
Accessed: 2012. diversity along an urban-rural gradient, in relation to any '
NBN Gateway. effects of allotment plot management styles i.e.
.
http://data.nbn.org.uk/gridMap/gridMap.isp?allDs=l traditional orwildlife-friendly.
&si-chSpKcv=NBNSYS0000005145.
GENERAL APPROACH
Accessed: 2012.
NBN Gateway. A questionnaire-based survey was used to detennine
:
http://data.nbn.org.iik/gridMap/gridMap.isp?allDs=l plot-holder attitudes to allotment management styles and
&srchSpKev=NHMSYS0000080204. the importance ofwildlife on the sites. From these data,
Accessed: 2012. individual plots across allotment sites in east Yorkshire
Scottish Natural Heritage. were identified to sample the epigeal invertebrates. In
www.snh.gov.uk/docs/B847683.pdf addition, plots were assigned as being either ‘traditional’
Accessed: 21/01/12. or ‘wildlife-friendly’ based on self-declaration. A range
;!
of environmental data were collected to detemiine the
li;
urban-rural gradient e.g. rural sites were likely to have a
i]
high percentage of sunounding farmland whilst urban
!
Urban Biodiversity: Successes and sites were likely to have a high percentage of
suiTounding hard cover. These data were infonued by
Challenges: Epigeal invertebrate
the results of the Biodiversity in Urban Gardens in
abundance and diversity on Yorkshire Sheffield (BUGS) project which examined, among other
things, garden invertebrate biodiversity (Smith e! al,
allotments
2006 a,b). Three pitfall traps, pooled per plot, were used
to sample invertebrate abundance and diversity in May
i?
S. Turnbull' & G. Scott“ and September 2006 on six pl6otsxf7roxm2ea-ch1o0f seven ,
sampling sites chosen (N = plots
'Ladysmith, Chapel Hill, Portmahomack, by Tain. 1V20 compromised/vandalized = 74) . These sites represented
lYH an urban-rural gradient and each site contained three
^Biological Sciences, University of Hull, Cottingham ‘traditionally’ managed plots and three organic, wildlife-
Road, Hull. HU6 7RX friendly plots, as identified from the questionnaires.
BIOLOGICAL DATA I
E-mail: [email protected] |
Pitfall trapping resulted in the collection of 11,718
|j
individual organisms; eight taxa were subject to fiirther
1^
ALLOTMENTS: FASCINATING HABITATS analysis. There was a significant difference in the mean :
number of individuals per allotment site (Fig 1). The -
After more than half a century of neglect and decline,
rural Driffield allotment site contained significantly
allotments are on the brink of a great revival (Foley,
lower overall invertebrate abundance compared to the
2004). Recent decades in particular have witnessed a
growing demand for allotments, partly linked to the Newland site in Hull city centre, which had the highest |
demand for healthy, pesticide-free food and an escape abundance. Although none of the other sites were f
statistically different from each other, there was a trend
from the pressures of modern, busy urban lives. The ,
image oftraditional plot-holders e.g. retired men may be towards an increase in mean abundance moving towards ,
the city centre. '
slowly changing. Allotment plots are increasingly
managed by young women and professional couples keen i
Beetles (Coleoptera) constituted 37.95%, woodlice
to grow organic crops or seek an escape from the daily
(Isopoda) 24.03% and spiders (Araneae), 16.93% ofthe v
grind (Buckingham, 2005; pers obs). In parallel to the
catch respectively. Urban sites tended to be dominated
increased interest in the socio-economic, health and by woodlice whilst beetles tended to be more common on (
recreational benefits of allotments, there is a growing some suburban and rural sites. The results for spiders and j
interest in the biodiversity value ofthese unique mosaics
the other five taxa, whose abundance ranged between
of intensively managed habitat (Gilbert, 1991).
0.73% - 8.96% of the total catch, showed mixed
However, to date there has been little published research
abundance across the urban-rural gradient (Fig 2).
which concentrates on them.
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With regard to overall invertebrate abundance in relation and require further exploration. However, in the case of
to management styles, the urban wildlife-friendly the slugs, it is likely that this group would be very
managed plots contained significantly higher abundance actively discouraged from allotments, due to their
compared to all other plots, except the urban traditional primary raison d'etre as a means ofgrowing food crops.
plots. The latter, whilst not statistically significant, did Slug pellets were the most common pesticide used, as
not contain such high abundance as the urban wildlife evidenced in the questionnaires, supporting this
plots. This therefore highlighted a trend towards conclusion.
increased abundance along the rural, suburban, urban
gradient, especially on those plots managed in a wildlife- Whilst management style suggests no overall difference
friendly way. in total invertebrate abundance, the differences at
geographic scale do appear to show some effect. The
The effects ofmanagement style on individual taxa gave higher abundance found on the wildlife-friendly
mixed results; different taxa dominated over differing allotment plots in the city centre may be due to a skewed
management styles. Beetles were significantly more effect ofthe high number ofwoodlice on these plots, as
abundant on traditionally managed plots. In contrast, the discussed above.
woodlice, slugs and snails (Mollusca) were significantly
more abundant on wildlife-friendly managed plots. Overall, the diversity of the taxa found suggests that
Spiders, opilione, millipedes and centipedes (Myriapoda) allotments are valuable habitats for epigeal invertebrates.
showed little difference in abundance in relation to The highest invertebrate diversity, found at the rural
management style. The most biologically diverse plots Driffield wildlife-friendly plots, corresponds with their
were managed in a wildlife-friendly way, with the low abundance and requires further study to tiy and
highest diversity found on a rural site at Driffield. explain the reasons. The environmental data gathered
Interestingly, this site also contained the lowest diversity suggests that the high proportion of fannland
on the traditionally managed plots. surrounding the allotment site may account for some of
the variation. Species arc likely to be able to disperse
DISCUSSION readily into the suiTounding habitat, unlike the more
This study has shown that there is considerable interest constrained urban habitat patches.
from allotment plot-holders in projects that recognize the
value of “their” allotments. Whilst older men still FUTURE WORK
dominate, there are an increasing number of community Further work is ongoing to identify the three most
groups, younger families and especially women, taking abundant taxa to species level from a rural, suburban and
on allotments. The latter are also more likely to place a urban allotment site respectively. Additional analysis of
higher value on the wildlife on their plots and sites, as the questionnaire data, environmental and biological data
shown by their commitment to manage their plots in an will be published separately in due course. This work
organic, wildlife-friendly way. will therefore provide some much-needed empirical data
on the epigeal invertebrate communities present on
The epigeal invertebrate taxa on the seven allotment sites Yorkshire allotments. This baseline infonnation could
studied showed a significant variation in both abundance then be used to explore further issues such as biological
and diversity along an urban-rural gradient. In contrast control methods or effects of climate change on crop
to what may have been expected, the urban sites growing on allotments.
contained the highest abundance whilst the rural sites
contained the lowest. Whist urban sites are likely to be CONCLUSIONS
subject to a higher range of anthropogenic pressures, The increase in popularity of allotments offers a great
each allotment site may be a small-scale biodiversity opportunity to study the wildlife benefits of such sites,
oasis, due partly to the lack ofother suitable suiTounding particularly in urban areas where greenspace is at a
habitatpatches compared to rural areas. premium. In order to advance these studies, it is
importantto engage with individual plot-holders.
The composition of the taxa found in the current study
was similar to that of the BUGS studies mentioned The epigeal invertebrate taxa found on these allotments
above, but the actual proportions of some of the taxa are similar to those found in garden studies, but the
were quite different. For example. Smith et al. (2006b) proportions of dominating taxa vary across the urban-
found that the three most abundant taxa of the pitfall rural gradient and with management styles. Abundance
traps were woodlice (45%), beetles (25%) and slugs was higher on urban plots, especially wildlife-friendly
(19%) respectively, whilst in the current study they managed ones, compared to both traditionally and
constituted 24%, 38% and 9% respectively. The most wildlife-friendly managed plots on mral or suburban
abundant taxa, the beetles, dominated the rural, and to sites. Invertebrate diversity was highest on some
lesser extent suburban, sites. The woodlice, however, wildlife-friendly rural plots, which also had low
dominated the urban sites, suggesting that they prefer abundance. Future work will help identify the specific
synanthropic environments. In addition, spiders species present and provide further clues to their
contributed 17% ofthe total catch, compared to less than ecological role on allotment sites.
5% BUGS
in the study.
The reasons forthese differences are likely to be many
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300
>
D
C
o
c
c
roa
RR SU
DR Driffield; HN Hunmanby; CT Cottingham; BV Beverley; BR Bridlington; BD Bude; NW Newland
Fig. 1. Mean numberofinvertebrates per Yorkshire allotment site (+ SE), based on individual plot totals (N=74),
grouped per urban-rural gradient. (RR=n,iral; SU=suburban; UU=urban.)
1600
Driffield Hunmanby Cottingham Beverley H Bridlington eBude Newland
Fig. 2. Total numberofeach invertebrate taxon from pitfall-traps on seven Yorkshire allotment sites.
28
REFERENCES sites have since been reclaimed by nature through
Buckingham, S. (2005). Women (re)construct the plot; natural succession.
the rcgen(d)eration of urban food growing. Area,
37, 2, 171-179. This rich industrial heritage ofScotland has resulted in
Foley. C. (2004). The Allotment Handbook. New over 10,000 hectares of land being listed as vacant or
Holland, London. derelict. These brownfield sites can be incredibly
Gilbert, O.L. (1991). The Ecology’ ofUrban Habitats. important for biodiversity, often supporting nationally
Chapman & Hall, London. important populations of rare and endangered
Marshall, T. (2009). Rural gardens, allotments and invertebrates, alongside other wildlife such as birds,
biodiversity. British Wildlife, 21,2, 85-95. reptiles, plants and lichens. With the loss of natural
Smith, R. M., Warren, P. H., Thompson, K. & Gaston, habitats in the wider countryside through agricultural
K. J. (2006a). Urban domestic gardens (VI): intensification and development, wild areas within the
environmental correlates of invertebrate species urban environment have become crucial to the survival
richness. Biodiversity’ and Consen>ation, 15, 2415- ofmany increasingly threatened species in the UK. As
2438. a result Open Mosaic Habitat on Previously Developed
Smith, R. M., Gaston, K. J., Warren, P. H. & Land (OMHPDL) was recently included as a UKBAP
Thompson, K. (2006b). Urban domestic gardens priority habitat.
(VIII): environmental correlates of invertebrate
abundance. Biodiversity and Consen’ation, 15, Brownfields are any site that have been altered by
2515-2545. human activity and are currently not fully in use
(CABE, 2006). They tend to be concentrated in urban
and former industrial landscapes but also include
quaiTies, spoil heaps, old railway lines and disused
Urban Biodiversity: Successes and airfields (Allan et al. 1997; Bodsworth et al. 2005;
Whitehouse, 2008; Riding et al. 2010). Brownfield
Challanges: Brownfields: oases of
sites provide linkages or ‘stepping stones’ between
urban biodiversity more natural areas of habitat and facilitate the
movement and mixing of individuals in a less
Craig R. Macadam' and Suzanne Z. Bairner“ favourable urban setting. Lack of management of
brownfields often creates an open mosaic of habitats
‘Buglife-The Invertebrate Conservation Trust, such as species rich grassland, bare ground and early
Balallan House, 24 Allan Park, Stirling, FK8 2QG successional habitats (Key, 2000; Bodsworth et al.
^ BTCV Scotland Natural Talent Apprentice 2005; Harvey et al. 2008). This, combined with a low
nutrient content ofthe soil which prevents fast growing
species becoming dominant, provides a continuity of
E-mail: craig.macadam(^buglife.org.uk
resources for invertebrates throughout the season
(Harvey et al. 2008). In addition, a mosaic of habitats
provides a home for a wide range ofspecies and allows
ABSTRACT
many to complete their life cycles within the same site
Despite their potential to support biodiversity, a strong (Bodsworth et al. 2005).
negative public image has been attached to brownfield
sites, with the conservation of these sites therefore It has long been recognised that brownfields may have
lagging behind other habitats. The inclusion of ‘Open as many associated Red Data Book (RDB) and
Mosaic Habitats on Previously Developed Land
(OMHPDL)’ as a UK Biodiversity Action Plan Nationally Scarce invertebrate species as ancient
woodlands (Jones, 2003). At least 194 invertebrate
(UKBAP) priority habitat has however resulted in a species of conseiwation importance, including 50 red
renewed focus on brownfields as important wildlife data book and 131 nationally scarce species, have been
habitats. The experiences of Buglife - The recorded from brownfield sites in the UK. This
Invertebrate Conservation Trust in both the Thames includes 50% ofrare solitary bees and wasps and 35%
Gateway and central Scotland have shown that of rare ground beetles (Bodsworth et al. 2005).
bUrKowBnAfiPelpdriosriitteys scpaenciessu,ppsoormtemoafnwyhircahrea,rescbaerccoemianngd sBpreocwinefs.ieldFsoralesoxasmupplpeo,rtthae sluaictek ooff UmKanBaAgPemeprnitoriotny
increasingly reliant on such sites as their natural
brownfield sites often provides a secure area for
habitats come underthreat. breeding birds such as skylark (Alauda an’ensis) and
INTRODUCTION grey partridge (Perdix perdi.x), that are often absent
from land under agricultural management. Many
The industrial revolution starting in the eighteenth features identified at long abandoned industrial sites
century transfonned the scenes of our towns and
can no longer be found in the managed and over-
countiyside. Central Scotland was at the heart of this fanned wider countiyside or even in over-tidied parks
revolution and many heavy engineering works and iron
(Bodsworth et al. 2005). Loss of natural habitat is
founders were based there. With the demise of these causing many species, including bumblebees, beetles,
industries across the country, their fomier premises butterflies and reptiles, to become increasingly reliant
have been left derelict. Many of these ex-industrial
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