Shared Landscapes: Optimising Conservation Strategies Using Tiger and Elephant Sympatry in India

: Asian elephants ( Elephas maximus ) and tigers ( Panthera tigris ) share the same landscape in India. Elephants, which range over 239,171 km 2 , occupy 45.5% of the 433,261 km 2 habitat that tigers inhabit. Equally, at least 40% of elephant corridors are used by tigers. A shared landscape offers opportunities for careful, integrated management strategies with shared resources. The species are protected differently in India, with tiger reserves being legal entities dedicated to the protection of tigers and their habitats, and Elephant Reserves being management units with no legal standing. With additional disparities in ﬁnancial supports to tiger reserves—which receive 10 times more money than elephant reserves—it is obvious that the elephant reserves are being treated inequitably. Since the two species coexist in the same landscapes, efforts to protect tigers can help to make up for elephant conservation gaps and optimise the use of conservation resources by tweaking a few management and policy practices. In addition, the overlay of tigers using elephant corridors can efﬁciently secure habitat linkages for both species.


Introduction
The tiger (Panthera tigris) and the Asian elephant (Elephas maximus) are India's largest terrestrial carnivore and herbivore species, respectively. Both species have reported significant global declines in their populations as well as areas of occupancy and are listed as 'Endangered' by the IUCN [1][2][3]. Both species are flagships of Indian conservation initiatives, having been conferred the status of National Animal and National Heritage Animal, respectively. India holds~70% of the global wild tiger population across a range exceeding 433,261 km 2 and~60% of the Asian elephant population over 239,171 km 2 , underlining its global significance [2][3][4]. Both species have fared remarkably well in the face of significant challenges including habitat loss and fragmentation, human-animal conflict, significant anthropogenic pressures such as grazing, non-timber forest produce harvesting, development pressure, and civil unrest in their ranging areas.
In India, tiger is protected under the 1972 Wildlife (Protection) Act of India, which confers the national animal legal protection against killing and destruction of its habitat. The habitats of this species are secured through a network of wildlife sanctuaries and national parks. The National Tiger Conservation Authority (NTCA), an autonomous authority constituted in India and charged with the responsibility of protecting tigers, has declared tiger reserves for the protection of the tigers [5][6][7]. Realising the need for larger landscapes, the tiger reserves subsume some of the sanctuaries and national parks and also include the intervening areas (as buffers) to offer larger conservation units for the benefit of the tiger. The NTCA has, thus far, notified 52 tiger reserves in India, covering 74,725 km 2 and aims to improve the ecological viability of tigers and their habitat [5]. From around 1411 in 2012, the number of tigers has stood at around 3000 since 2019 [6], a tribute to the success of the programme.
Much like the tiger protection, elephants in India are a protected under schedule I of the 1972 Wildlife (Protection) Act of India. As weith tigers, the elephant habitats are protected under this act by a network of wildlife sanctuaries and national parks. Following the success of 'Project Tiger' in 1992, the Union Government of India initiated the 'Project Elephant' to protect elephants and their habitat. The 'Project Elephant' declared a series of 'Elephant Reserves' but unlike the tiger reserves, the large intervening spaces between sanctuaries and national parks are not 'legally protected' and do not have protection under the 1972 Wildlife (Protection) Act. Thus, the elephant reserves are simply management units without any legal mandate but formally notified by various State Governments. The elephant populations have remained relatively stable, growing from 26,000 in 2007 to 30,000 in 2017 [8]. However, this fact must take into account the long lifespan and inter-generational span of the latter as compared to the former.
India now has 31 elephant reserves spread across 76,508 km 2 and are an administrative category where only the protected areas within are managed by the forest department with much of the buffer and most corridors lying outside direct biodiversity management [1]. The gazette notifications of two more elephant reserves, viz. Terai Elephant Reserve (Uttar Pradesh) and Agasthmalai Elephant Reserve (Tamil Nadu), are under the process and will add about 4247 km 2 to the area under elephant reserves. Less than a third of the elephant reserves are part of the Protected Area network (PAs) while 30% are beyond the control of the forest administration, posing management and governance challenges of various dimensions [1].
While the tiger is undoubtedly the flagship of Indian wildlife conservation, both in terms of registering a significant growth in their numbers, through legal protection of areas and allocation of adequate financial resources, elephants have not received the same legal and financial support. While changes in tiger [2,9] and elephant [10,11] ranges as well as habitat connectivity [12,13] are well documented, little has been reported on the possible synergistic management models involving the two species. We explore the possible benefits both species may derive from such synergistic planning and even management. This article investigated species' range overlaps, similarity of conservation threats and conservation practices, and arrive at certain conservation implications of this sympatry which could be useful as a management tool.

Methodology and Approach
Global distributions of both species were sourced from the IUCN Red List database [2,3] and clipped to include Indian boundaries only. The extant distribution ranges of both species were considered for analysis and discussion. Data used for boundaries of protected areas, elephant reserves and tiger reserves were sourced from notification gazettes and government websites [14,15].
The study analysed the extent of habitat intersections/range overlaps of the two species, and the status of prevalent legal protection afforded to them. The range maps generated for tiger ( Figure 1) and elephant ( Figure 2) were used to investigate the range intersection for both species and area covered by legally protected habitats. Range overlap or the area of cohabitation, were calculated from range intersections in respective landscapes. For example, range overlap for both species in southern landscapes were the calculated intersections of the tiger range in Western Ghats tiger landscape and elephant range in southern elephant landscape (Zone) ( Table 1). Percentage overlap of elephant landscapes with tiger landscapes were calculated as percentage area of the elephant landscape inhabited by tigers and vice versa (Table 1). Annually cumulated data were used for analysing annual or decadal changes in protected area notifications, area of legally secured habitats, etc. All analyses and mapping were performed using QGIS 3.22.5 [16] (with plugins as NNJOIN, RAT, etc.) and MS Excel.

Range Overlaps of Asian Elephants and Tigers in India
According to the recently updated IUCN range map, the tiger, in India, covers 13.18% (433,261 km 2 ) of the country's landmass ( Figure 1) which is 36.75% of its global extent. The Indian tiger range is spatially distributed over five landscapes, viz. the Central India and Eastern Ghats (1033 tigers), Western Ghats (981 tigers), Shivalik hills-Gangetic plains (646 tigers), Sundarbans (88 tigers) and, the North-East hills and Brahmaputra valley (219 tigers) [5].
The range of the Asian elephant range in India spreads over the north-eastern, central, north-western and southern elephant landscapes also called elephant zones. The elephant, as per IUCN, is distributed over ~239,171 km 2 in India, (Figure 2) which is ~52% of its total global range. More than 41% of the elephant's range is in the north-eastern landscape followed by the central and southern landscape. Only 2.6% of its total range is located in the north-western landscape making its north-western range quite small. As per the latest estimates these landscapes sustain ~30,000 wild elephants-highest in the southern zone (14,612), followed by North-Eastern India (10139), Central India (3128) and North-Western India (2085) [17].

Range Overlaps of Asian Elephants and Tigers in India
According to the recently updated IUCN range map, the tiger, in India, covers 13.18% (433,261 km 2 ) of the country's landmass ( Figure 1) which is 36.75% of its global extent. The Indian tiger range is spatially distributed over five landscapes, viz. the Central India and Eastern Ghats (1033 tigers), Western Ghats (981 tigers), Shivalik hills-Gangetic plains (646 tigers), Sundarbans (88 tigers) and, the North-East hills and Brahmaputra valley (219 tigers) [5].
The range of the Asian elephant range in India spreads over the north-eastern, central, north-western and southern elephant landscapes also called elephant zones. The elephant, as per IUCN, is distributed over~239,171 km 2 in India, (Figure 2) which is~52% of its total global range. More than 41% of the elephant's range is in the north-eastern landscape followed by the central and southern landscape. Only 2.6% of its total range is located in the north-western landscape making its north-western range quite small. As per the latest estimates these landscapes sustain~30,000 wild elephants-highest in the southern zone (14,612), followed by North-Eastern India (10139), Central India (3128) and North-Western India (2085) [17].
Elephants use 45.5% of the tiger range, while tigers occupy 25.1% of the estimated elephant extent (Table 1, Figure 3). The overlap between the ranges of Asian elephant and tigers in India is a sprawling 108,712 km 2 , with varying degrees of overlap across the regions (Table 2, Figure 3). In North-Western India, the proportion of elephant zone that overlaps with the tiger landscape is the highest (79.8%), while the overlap of tiger landscape with the elephant zone is the least (14.5%) among all the regions. The highest overlap of tiger landscape with elephant zone was in the southern part of the country.
Elephants use 45.5% of the tiger range, while tigers occupy 25.1% of the estima elephant extent (Table 1, Figure 3). The overlap between the ranges of Asian elephant a tigers in India is a sprawling 108712 km 2 , with varying degrees of overlap across the gions (Table 2, Figure 3). In North-Western India, the proportion of elephant zone t overlaps with the tiger landscape is the highest (79.8%), while the overlap of tiger lan scape with the elephant zone is the least (14.5%) among all the regions. The highest ov lap of tiger landscape with elephant zone was in the southern part of the country.   Moreover, 74,725 km 2 is notified as tiger reserves [14] which encompass some of the above mentioned protected areas, other categories of forests (territorial, protected forests, forests under state forest corporations, etc.) and revenue land in its core and buffer zones.
It is evident that the total area legally secured for the conservation of wildlife and its habitats increased after notification of the 1972 Wildlife (Protection) Act (Figure 4). Under the aegis of Project Tiger of the Government of India, tiger reserves were first designated in 1973-1974, and registered a gradual rise in their coverage after 2005 with a surge in prioritisation of tiger conservation in the country.

Protected Area Network Overlap between Tiger and Elephant Distribution
Currently, 5.26% (173,054 km 2 ) of the Indian land mass is conserved and managed as a network of national parks, sanctuaries, community reserves and conservation reserves-the categories of protected areas [15] defined under the Wildlife (Protection) Act of 1972. Moreover, 74,725 km 2 is notified as tiger reserves [14] which encompass some of the above mentioned protected areas, other categories of forests (territorial, protected forests, forests under state forest corporations, etc.) and revenue land in its core and buffer zones.
It is evident that the total area legally secured for the conservation of wildlife and its habitats increased after notification of the 1972 Wildlife (Protection) Act (Figure 4). Under the aegis of Project Tiger of the Government of India, tiger reserves were first designated in 1973-1974, and registered a gradual rise in their coverage after 2005 with a surge in prioritisation of tiger conservation in the country.  Elephant reserves, unlike tiger reserves, are not legal entities under India's Wildlife (Protection) Act of 1972. Currently, 31 notified elephant reserves (two more are under the process of notification) cover 76,508 km 2 , that includes 17,970 km 2 (23.4%) under protected areas [18]. However, out of the total elephant range in India, i.e., 239,171 km 2 , only 12.2% (29,071 km 2 ) of the area is a legally protected area, and an additional 4.96% (11,862 km 2 ) is a buffer of tiger reserves ( Figure 5).
Diversity 2022, 14, x FOR PEER REVIEW 7 of 14 (29,071 km 2 ) of the area is a legally protected area, and an additional 4.96% (11,862 km 2 ) is a buffer of tiger reserves ( Figure 5).

Elephant Corridors and Overlap with Tiger Distribution
We also looked at the well-established elephant corridor network of India [13] with tiger presence or usage. Corridors are 'linear two dimensional landscape elements that connect two or more patches of wildlife (animal) habitats that have been connected in historic times' [19]. The corridors have gradually become constricted and reduced to narrow and short passages with growing human population in the country. An analysis of data shows that almost 40% of all elephant corridors in India have tiger presence. Tiger presence was recorded in the corridors as follows: ~91% of north-western, ~62% of southern, ~30% of north-eastern and only 4% of central elephant zones in India (Figure 6, Table 3).

Elephant Corridors and Overlap with Tiger Distribution
We also looked at the well-established elephant corridor network of India [13] with tiger presence or usage. Corridors are 'linear two dimensional landscape elements that connect two or more patches of wildlife (animal) habitats that have been connected in historic times' [19]. The corridors have gradually become constricted and reduced to narrow and short passages with growing human population in the country. An analysis of data shows that almost 40% of all elephant corridors in India have tiger presence. Tiger presence was recorded in the corridors as follows:~91% of north-western,~62% of southern,~30% of north-eastern and only 4% of central elephant zones in India ( Figure 6, Table 3).

Discussion
Large animals are consistently among the most threatened species and are at greater risk of extinction than smaller species [20,21]. Tigers and Asian elephants face similar threats of habitat fragmentation and loss, poaching and retaliatory killings, across its range in India [2,3]. Natural forest loss and fragmentation are irreversible in nature in the short term, and pose a direct impact on both species, especially elephants. In India, the forest cover declined alarmingly by 21.49% between 1930 and 1975 and further deteriorated by 3.19% between 1975 and 2013, leading to forest loss in all the four elephant landscapes of the country. The southern landscape faced the highest forest lost (13,084 km 2 ) followed by the north-eastern (10,188 km 2 ), central (5614 km 2 ), and north-western (4030 km 2 ) landscapes in the past eight decades [22]. However, forest cover has witnessed marginal improvement in few states of the southern landscape [23]. Forest degradation and fragmentation impact the elephant's ecological and biological needs while impeded corridors limit elephant movement and seasonal local migration [12]. Elephant corridors in India have risen by 25% in a decade (2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) reflecting habitat loss [13].
The ever expanding area of protected tiger habitats has considerably contributed to the improvement of tiger habitats and population status of the species. The effectiveness

Discussion
Large animals are consistently among the most threatened species and are at greater risk of extinction than smaller species [20,21]. Tigers and Asian elephants face similar threats of habitat fragmentation and loss, poaching and retaliatory killings, across its range in India [2,3]. Natural forest loss and fragmentation are irreversible in nature in the short term, and pose a direct impact on both species, especially elephants. In India, the forest cover declined alarmingly by 21.49% between 1930 and 1975 and further deteriorated by 3.19% between 1975 and 2013, leading to forest loss in all the four elephant landscapes of the country. The southern landscape faced the highest forest lost (13,084 km 2 ) followed by the north-eastern (10,188 km 2 ), central (5614 km 2 ), and north-western (4030 km 2 ) landscapes in the past eight decades [22]. However, forest cover has witnessed marginal improvement in few states of the southern landscape [23]. Forest degradation and fragmentation impact the elephant's ecological and biological needs while impeded corridors limit elephant movement and seasonal local migration [12]. Elephant corridors in India have risen by 25% in a decade (2004-2015) reflecting habitat loss [13].
The ever expanding area of protected tiger habitats has considerably contributed to the improvement of tiger habitats and population status of the species. The effectiveness of management and governance of the tiger reserves improved significantly after the amendment of the 1972 Wildlife (Protection) Act in 2006 leading to several reforms in the approach of tiger conservation primarily bringing about the formation of the National Tiger Conservation Authority [6]. This has further reinforced the protection of the species in the wild through increased targeted habitat coverage and fortified legal bases. Additionally, this has also provided protection to many sympatric species.
Although the total area of notified elephant reserves has increased since 2002, the number and extent of protected areas within the elephant reserves has not expanded much. The increasing reserve areas and its current legal coverage as protected wildlife habitats had a negative relationship (r = −0.579). This implies a stagnation of the protected areas within an expanding elephant reserve. This contrasts with an increasing interest in the protection of elephant corridors by scientists and civil society which have been increasingly imposed on governments by judiciaries. For example, a public interest litigation case for the securement of an elephant corridor, the Madras High Court endorsed an order of the Tamil Nadu state government to notify the Sigur elephant corridor, and this decision was further upheld by the Supreme Court of India in October 2020 which ordered the removal of 39 illegal resorts from the elephant corridor in the Sigur plateau landscape. In Habitat loss and fragmentation can be arrested by declaring areas as protected [24] but elephants require much larger areas than what is afforded by Indian PAs to fulfil their ecological needs. In the approximately 700 national parks and sanctuaries, 96% of the PAs are less than 1000 km 2 and only 0.3% of PAs are larger than 5000 km 2 [25]. The area and extent of most of the PAs is inadequate for elephant conservation due to requirement of large home range sizes-between 550-700 km 2 for female clan in tropical deciduous forests in Southern India and between 188 to 407 km 2 for different male and female clans in North-Western India [26,27]. Despite this limitation, the importance of PAs cannot be ignored as they offer safeguards against habitat degradation and fragmentation [24] which are major threats for elephants [13]. Tiger reserves are the focus of much of India's conservation effort,~55% of which comprise protected areas (core area of tiger reserves are national parks and sanctuaries). The budget allocated by the Government of India for tiger reserves is about 10 times the budget for elephant reserves. In the last six years (2017-2023), the average budgetary outlay for Project Tiger was USD 3.81 ± 0.9 million while it was a paltry USD 0.38 ± 0.052 million for Project Elephant (http://www.indiabudget.gov.in/ accessed on 26 July 2022). Thus, the tiger reserves are better maintained and managed to contribute to protection of larger landscapes [9,28] as manifested from meagre forest loss of approximately 0.3% and 0.5% inside and within 10 km around the boundary of tiger reserves [28,29]. Consequently, tiger reserves augur well for conservation of biodiversity, including elephants, in overlapping ranges.
Traditionally, India has conserved species by increasing the coverage of national parks, sanctuaries, community reserves and conservation reserves which are protected areas that have sanctity within the Wildlife (Protection) Act of 1972. There have also been several policy documents and committee recommendations of the Union Ministry which in the past have suggested securing elephant landscape that lies outside such zones by rationalising elephant reserve boundaries for human use with Let-go, Slow-go and No-go zones [1]. A third mechanism has been tried out in the state of Meghalaya where a Wildlife Trust of India project with the Garo Hills Autonomous District Council (GHADC)-an institution set up under the sixth Schedule of the Constitution of India, has set up a slew of Village Reserve Forest for elephant corridor and habitat conservation which lies outside the purview of the 1972 Wildlife (Protection) Act [30][31][32]. These 42 km 2 of habitat have used particular traditional and hereditary protection mechanisms such as availability for sacred groves and the administrative provisions of the GHADC in order to manage community land for elephants and indeed for the gibbon and certain bird species. However, the efficacy of these to provide linkages to the low density source and sinks of tigers in the region has not been tested out.
Therefore, we suggest a few measures that would improve the conservation of both the species by encouraging multi-species conservation in tiger landscapes: (A) In tiger reserves where tigers and elephants co-exist, introduce elephant conservation and management measures as well, which would allow existing management and monetary resources in the reserves to also support elephant conservation. This would require specific management measures that may not be addressed in current schemes as habitat management, food requirements and security needs from threats as the poaching, snaring, etc. of elephants differ from tigers. Tiger reserve management plans will then need to be reanalysed on the basis of elephant management measures to look at additions or changes required. One such successful co-management example is in Kaziranga Tiger Reserve (Assam, India) which has recovered the one-horned rhinoceros' (Rhinoceros unicornis) populations in the protected area [33]. (B) It is suggested that in cases where states have proposed elephant corridor management in areas where tigers are present, these be considered as linkages between sources and sinks of tiger populations, and thus management measures here be calibrated for both species. (C) It is recommended that in North-Eastern India where the protected area coverage is low and both elephants and tigers co-exist in several areas, the concept of community protection using traditional rights and autonomous council rights be viewed for protecting landscapes for both species.
All this is even more relevant with the projected changes in climate, thereby leading to temperature and water imbalances that would, for example, alter Asian elephant distribution in the Indian subcontinent [34]. The projections indicate loss of habitat in the human-dominated regions, such as Central-Eastern (Eastern Ghats) and the Southern Western Ghats of India and in the relatively flat areas of the Himalayan region [34]. Hence, probabilities of elephant range overlapping with much more areas of tiger ranges in future are high, which demands for designing an effective protected area network to secure both the keystone species. We recommend scientifically designing multiple-species protected areas/reserves to support viable populations and reduce extinction risks for these two species.