Method
The data found in figure 5 was tested for normality
using the Anderson darling test for normality which
gave a P value of below 0.005, meaning that data
is not normally distributed. Because of this, the
non-parametric test Mann Whitney was used to find
a significant difference in species richness between T.
baccata and R. ponticum. From this a P value of 0.108
was achieved, meaning that no significant difference
was found between the species richness’ between T.
baccata shrub and R. ponticum shrub. This is generally
not supported by previous research, although the
impact that invasive species may have has been
disputed. Vilà at al. (2015) found that plots containing
non-native plants had lower native plant and lower
animal species richness within them, compared to
paired uninvaded control plots. Our research suggests
that shrub species has little impact on the number of
species observed, native or not. Although it should be
noted that time of year may have had some impacts
on species richness observed, with species such as
hedgehogs being in hibernation for the majority of
the study period (RSPCA, 2019).
The data found in figure 6 was tested for normality
using the Anderson darling test which gave a P value
of below 0.005, meaning that data is not normally
distributed. Because of this the non- parametric Mann
Whitney test was used for further analysis. This gave
a P value of below 0.000 which indicates that there
is a significant difference in the activity between the
two shrubs. H02 can be rejected as a result of this
analysis, meaning that activity was different between
the native and non-native species. In fact, based on
the data in figure 6, activity was generally higher in R.
ponicum than T. baccata, potentially supporting the
idea that R. ponticum could be used as a conservation
tool.
The Anderson-Darling test for normality was
conducted on the mouse print data in figure 7 which,
once again, found that the data was not normally
distributed. Because of this the non-parametric test
Man Whitney was used to determine if significant
96
data was collected. In this instance, a P value of
0.042 was found. This shows a significant difference
between the data found in R. ponticum and T. baccata
meaning that we also reject H03. This once again
suggests that activity was significantly higher in R.
ponticum, meaning R. ponticum has the potential
to be a conservation tool for these small mammals.
A previous study by Malo et al. (2013) had similar
findings, that R. ponticum allowed for higher mice
abundances than open woodland areas. The paper
suggests several reasons for this finding, including
increase in protection from aerial predation which
is more difficult in shrub areas (Southern and Lowe,
1968) as well as improved foraging efficiency as
found by Fedriani and Manzaneda (2005).
An initial reaction to increased populations around R.
ponticum would be that it is a good thing, not only
would this mean that R. ponticum could be used for
the conservation of these populations, but increased
mice populations would provide more prey for land
dwelling predatory species that are at risk. With
Mathews et al. (2018) suggesting that one in five
mammals in the UK are at risk of extinction within
the next decade, the potential use of well managed
non-native species to improve the conservation of
these species seems promising (Schlaepfer, Sax and
Olden, 2011).
However, the negative impacts of R. ponticum must
be considered before new management plans are put
in place. One key issue with suggesting such changes
is the current outbreak of Phytopthora ramorum,
a fungus like disease which is most commonly
controlled by the complete removal of the plant and
repeated herbicide applications to prevent regrowth
and reinfection (Willoughby et al., 2015). How R.
ponticum impacts the composition of woodland
plant species also cannot be ignored, as R. ponticum
causes serious forest degradation and reduced seed
germination. Incorrect management can potentially
amplify these effects. The increased mouse activity in
these areas may also further affect seed germination,
with the increased activity leading to increased
foraging and feeding on seeds produced.