How representative are the study areas?

Chapters 2, 3 and 4 in this thesis focus on single region studies – the UK in Chapters 2 and 3, and a large biosphere reserve in Mexico in Chapter 4. The findings from these case studies, however, clearly have implications beyond the shores of the UK and the borders of the SGBR in Mexico.

Levels of protection, governance and the numbers of extirpations, introductions and colonisations in both the UK and Mexico are similar to the averages for Europe and the Americas respectively (Table 6.3), indicating that the distributional changes in both countries could be typical for their region, although, like all countries, their avifaunas have unique features. For example, the UK’s geographical position makes it well placed to receive vagrant birds (Lees & Gilroy, 2009), its high allocation of resources for conservation projects have allowed for the re-introduction of native bird species such as the Western Capercaillie Tetrao

urogallus and the White-tailed Eagle Haliaeetus albicilla, thus ‘reversing’ previous extirpations,

and the era of colonialism and historical desire of British landowners to keep ornamental waterbirds on their ponds has resulted in a high number of introductions (e.g. Sutherland & Allport, 1999). In Mexico, the majority of the established non-native species are present having spread southwards from populations introduced into the USA by European settlers. Despite these individualities, however, a number of the patterns are likely to apply elsewhere.

I consider it likely that the patterns of PA association shown by colonising species in the UK can be extrapolated to other countries. Positive trends of species targeted by

conservation measures across Europe (Donald et al., 2007; Sanderson et al., 2016) and North Africa (Kleijn et al., 2014) demonstrate the effective performance of PA networks (including in the UK) per se, and I found colonisation to be positively correlated with the amount of

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that such networks are important for species expanding their range across the World; although the relative importance of PAs for species expanding their distributions might be related to the degree to which wildlife faces pressures (e.g. persecution, farming

intensification) in non-protected land. It may also be related to the policing and management of PA networks. Strong associations between colonisers and PAs has been demonstrated in the UK, which has one of the highest-intensity farming regimes in Europe (Donald et al., 2001) combined with a relatively large amount of protected land (Table 6.3).

Table 6.3 Measures of protection, quality of governance and rates of species turnover in the

UK and Mexico and the averages for their respective continents. Regional data (for Europe, Americas and World) is calculated as the average across the countries which were included in the Chapter 5 study.

Numbers from 1815-2015 (colonisations from 1945)

Country/Region PA% Governance Extirpations Introductions Colonisations

UK 28.43 1.7 4 10 8

Mexico 12.92 0.2 9 7 10

Europe 20.31 0.85 7.24 4.13 7.89

Americas 20.61 0.12 3.64 7.81 4.30

World 18.84 0.32 5.49 6.04 4.51

Distributional patterns of range-expanding non-native species are also informative beyond the UK. The spread of non-native populations of Sacred Ibis Threskiornis aethopicus, Purple Swamphen Porphyrio porphyrio and Chilean Flamingo Phoenicopterus chilensis has been associated with unprotected land in continental Europe (Appendix 2J) and on a broader scale there appear to be fewer introductions in regions with higher amounts of protected land (Table 5.5).

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Globally, there are 669 Biosphere Reserves in 120 countries (unesco.org), providing a model of protection based on core area(s) surrounded by a buffer zone. Thus the findings of Chapter 5 are clearly of wider importance. Although the buffer zones themselves, which correspond to IUCN Category VI (Table 1.1), might not necessarily contain greater species richness than nearby unprotected, or transition land, they serve a purpose in sheltering core zones, which I have shown are important for species undergoing global declines. Core zones within other Biosphere Reserves in Mexico contain threatened bird species such as Great Curassows Crax rubra (Sian Ka’an Biosphere Reserve) and Horned Guans (El Triunfo Biosphere Reserve), and species from other taxonomic groups such as Jaguars Panthera onca (Sierra de Santa Marta Biosphere Reserve; CONABIO, 1995) and Monarch butterflies Danaus plexippus (Monarch Butterfly Biosphere Reserve). Beyond Mexico, Biosphere Reserves and their core zones harbour globally endangered species such as Spanish Imperial Eagles Aquila adalberti (Castro Verde Biosphere Reserve), Snow Leopards Panthera uncia (Khangchendzonga Biosphere Reserve, India; cpreec.org), Giant Pandas Ailuropoda melaleuca (Baishuijiang National Nature Reserve) and important species assemblages – the Savegre Biosphere Reserve in Costa Rica hosts 54% of the country’s mammals and 59% of its birds

(nationalgeographic.com). Broad research on whether these species are found

disproportionately in core zones is missing, although it appears true at least for Military Macaws, Horned Guans (González-García & Abundis, 2005) and Monarchs (Vidal & Rendón- Salinas, 2014). In most cases, core zones undergo less land clearing and are affected by less human disturbance than nearby buffer zones (Walker & Solecki, 1999; Chowdhury, 2006; Vester et al., 2007; Xu et al., 2016), which supports the hypothesis that they are important for species which are threatened by human activity.

As PAs which promote sustainable development (Price, 2002) and the interaction of biological and cultural diversity (Bridgewater, 2002), however, the importance of Biosphere Reserves goes beyond measures of species richness or the presence of important individual species. Biosphere Reserves, rather than being protected from people, actively depend on the people living within them playing participatory roles in the management of the reserve (Price, 2002). Stakeholder participation was identified as the most important aspect influencing the ‘success’ (as measured by expert opinion) of the Biosphere Reserve network (Van Cuong et al., 2017). Mexico is one of many emerging economies where competition for resources is high, and allocation of resources for conservation is relatively low. PAs within Mexico (Blackman et

al., 2015), in neighbouring countries (e.g. Guatemala - Bonham et al., 2008) and globally

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1999)) can become ‘paper parks’ (see Introduction). In such areas, community engagement, participation and understanding might be as appropriate as measures of PA success as purely biological metrics.