The Effects of Trophy Hunting of African Lions (Panthera Leo) on Their Population in Tanzania and Zimbabwe, While Comparing Threats with Kenya’S Lion Population

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The Effects of Trophy Hunting of African lions (Panthera leo) on their Population in Tanzania and Zimbabwe, While Comparing Threats with Kenya’s Lion Population

Tonya Manley

ENVS 190-Thesis

December 13, 2018

African lion (Panthera leo) with dark mane. Photo Credit: Dr. Michelle Stevens

Abstract The African lion (Panthera leo) is an apex predator that is protected by conservation efforts in Kenya, Tanzania, and Zimbabwe (Williams, 2017). While the lion is under protection, they are also trophy hunted in Tanzania and Zimbabwe, raising possible issues to their population numbers (Loveridge et al., 2007; IUCN, 2016; Packer et al., 2011). There are benefits to trophy hunting lions such as community safety, local economies benefiting, conservation efforts for lions, and livestock owners (Lindsey et al., 2007 and 2013; IUCN,

2016; Packer et al., 2006). However, there are also disadvantages to trophy hunting lions such as population decline, genetic problems, tourism, ecological disruption, and cultural connections (Bauer et al., 2016; (Trinkel and Angelici, 2016; IUCN 2014; Hazzah et al.,

2009). The purpose of this paper is to present case studies to help determine the current approaches of trophy hunting lions that may affect population size and potential solutions such as age restrictions, limiting quotas, community education and conservation. Kenya,

Tanzania and Zimbabwe’s African lion populations will be examined to indicate if trophy hunting has an effect, and if other threats contribute to a population decline. Kenya’s lion population remained stable or increased in certain areas since 1996, but are facing threats including protection against land conversion and human-wildlife conflict (Lindsey et al.,

2017; Ogutu et al., 2016). The case studies suggest that Tanzania’s and Zimbabwe’s lion populations are effected by trophy hunting, along with other threats such human-wildlife conflict and bushmeat (Lindsey et al., 2017; Loveridge et al., 2007 and 2016; Packer, 2011).

Conservation and management practices are a must for assessing the lion population and making sure it is healthy enough for the population to regenerate.

Table of Contents

Introduction ...... 1 Materials and Methods ...... 3 Background ...... 3 Threats ...... 8 Advantages ...... 9 Protection against Conversion of Land ...... 9 Community safety ...... 10 Conservation ...... 11 Disadvantages ...... 12 Genetic Problems ...... 12 Ecological Importance ...... 13 Cultural Rituals ...... 13 Tourism ...... 14 Rules and Regulations ...... 15 Kenya ...... 15 Tanzania ...... 15 Zimbabwe ...... 18 Imports/Exports of Lion Trophies ...... 18 Case Studies ...... 21 Zimbabwe Case Studies ...... 21 Tanzania Case Studies ...... 25 Kenya Case Studies ...... 28 Case Study Comparing Zimbabwe, Tanzania and Kenya’s Lion Population ...... 29 Discussion and Recommendations ...... 32 Conclusion ...... 35 Literature Cited ...... 37

Introduction Trophy hunting is a recreational sport where hunters go after specific megafauna, typically large or impressive ornamented males (Darimont et al., 2017). Trophy hunting is large in Africa, consisting of five specific species including the Cape buffalos (Syncerus caffer), African elephants (Loxodonta), African leopards (Panthera pardus), African lions

(Panthera leo), and Rhinoceros (Rhinocerotidae) (Caro and Riggio, 2014). The big five populations have experienced declines across the African continent, but these species continue to be high value in game sales because of trophy hunting (Caro and Riggio, 2014).

Lions are particularly desirable to hunters because of the real danger involved, meaning that the lion may attack without being provoked and is considered the best of the big five in the trophy hunting community (Casamitjana and Tsang, 2017).

The African lion (Panthera leo) is an apex predator that is protected by conservation efforts in Kenya, Tanzania, and Zimbabwe (Williams, 2017). While the lion is under protection, they are also trophy hunted in Tanzania and Zimbabwe, raising possible issues to their population numbers (Loveridge et al., 2007; IUCN, 2016; Packer et al., 2011). There are benefits to trophy hunting lions such as community safety, local economies benefiting, conservation efforts for lions, and livestock owners (Lindsey et al., 2007 and 2013; IUCN,

2009).

The goal of this project is to indicate whether trophy hunting practices are decreasing the African lion’s population and if current management in Kenya, Tanzania and

Zimbabwe have effective conservation efforts to keep their population stable or increasing.

The purpose of this paper is to present case studies to help determine the current approaches of trophy hunting lions that may affect population size and potential solutions such as age restrictions, limiting quotas, community education and conservation. Kenya,

Tanzania and Zimbabwe’s African lion populations will be examined to indicate if trophy hunting has an effect, and if other threats contribute to a population decline. Does trophy hunting African lions effect their population in Tanzania and Zimbabwe? This research will help in assessing the actions needed for protecting the African lion’s population.

The literature review project is to assess the debate of trophy hunting lions by looking at many of the possible complications and advantages of the sport in the African countries including Tanzania and Zimbabwe, while comparing Kenya that has banned trophy hunting. Lion populations are in a dilemma from indiscriminate killing, habitat loss, prey depletion, illegal trade and trophy hunting (Bauer et al., 2016). Although trophy hunting may be a threat to lion populations, it can be more easily controlled than other threats, so assessing its effects on their population is crucial in creating rules and regulations for the sport (Creel et al., 2016). Since 1996-2016, these threats have resulted in the African lion’s status being vulnerable with great declines in their population

(MacDonald et. al., 2017). The Endangered Species Act states the African lions in Western and Central Africa are endangered, with Eastern and Southern Africa as threatened in 2015 recorded by U.S. Fish and Wildlife Services (Creel et al., 2016). According to the

International Union for Conservation of Nature (IUCN), the African lion population has been decreasing by 43% between 1993 and 2014 throughout the continent of Africa (Bauer et al., 2016). The IUCN estimates around 23,000-39,000 mature African lions are left in the

wild and most of the population lives in East and South Africa. When trophy hunting is poorly managed, it can cause negative impacts on their population such as social disruption, genetic effects, population declines and age/sex structures (Milner et al., 2007;

Packer et al., 2011). Conservation and management practices are a must for assessing the lion population and making sure it is healthy enough for the population to regenerate.

Materials and Methods This paper evaluates the advantages and disadvantages to trophy hunting lions, while examining pressures of trophy hunting on the lion’s populations. Scientific information from peer reviewed literature will be analyzed to assess the questions asked. The necessary tools for the literature review is a computer, reliable internet service and the library. Search terms such as “trophy hunting lions” and “conservation biology for African lions” was used to focus on limiting subjects that will help narrow down the topic. The literature being analyzed is between 1972 and 2018, but most information is from the

2000s and up. PLoS One and Conservation Biology articles are heavily used to asses case studies. This research will involve collecting published articles, books, and websites to address the topic of trophy hunting African lions. Websites to collect this data include google scholar, worldcat and Sacramento States databases.

Background The African lion is the parent species of the West African lion subpopulation, which is critically endangered and the subspecies only in Asia, the Asiatic lion (Panthera leo ssp. persica), which is endangered (Bauer et al., 2016; Figure 1). The African lion’s population has decreased alongside with habitat loss, resulting in 10 stronghold populations with more than 500 individuals (Creel et al. 2016; Bauer et al. 2015). The

African lion’s habitats are grassy plains, savannahs, and open woodlands with bushes. The plains are prairies of grassy land without many trees or vegetation, but high grasses to blend in from prey. An African savanna is a region of grassy plains in tropical and subtropical regions with very few trees. Open woodlands are an ecosystem of low-density forest with many open areas for sunlight and some shrubs. The lions range originally covered most of Africa, parts of Europe and Asia, but are now in very confined territories in sub-Saharan Africa and a small population of Asian lions in India’s Gir Forest (Bauer et al.,

2016; Trinkel and Angelici 2016; Figure 2). Devastating threats to the lion’s population has resulted in their extinction in 12 different African countries and possibly 4 more (Bauer et al., 2016). Tanzania has the largest population of African lions consisting of 30-50% of their overall population in the whole continent, but trophy hunting has been a contributing factor in their population declining (Lindsey et al., 2013). The African lion’s subpopulation in West Africa is the most critical with less than 500 individuals and less than 250 that are mature adults (Henschel 2014; Trinkel and Angelici, 2016).

Figure 1: African lion at Sacramento Zoo (Tonya Manley; Figure 1).

Figure 2: African lion’s historical distribution vs. present distribution and areas where there may be lions, temporary, or recently extirpated in Africa (Trinkel and Angelici,

2016; Figure 2).

Lions are socially dependent wild cats that rely on groups called prides that include up to three males, a dozen females and their young (Mosser and Packer, 2009). The prides numbers can consist of fewer than four or more than 40 lions and cubs. The young females tend to stay within the pride they are in and raise a family of their own if they make it to maturity, while the young males leave and take over a new pride by challenging the head male. If the males are unsuccessful at winning over the pride, they can become nomads and mating opportunities are rare (Mosser and Packer, 2009). Male lions can sometimes join other males called a coalition, consisting of one to nine individuals (Mosser and Packer,

2009). These males do have a chance at mating neighboring females or can become a part of a pride. If they successfully join a pride, there is a possibility they will kill any male cubs or force females out of the pride if they are not sexually mature. Takeover of the prides by new males results in an increase in cub mortality, which raises issues with trophy hunting when a leader is killed from a hunter or other human-wildlife conflicts (Bertram, 1975).

Competition for females is an important process in a lion’s social behavior, with socially mature males chosen more often than immature males (Loveridge et al., 2007). A darker colored mane and size of the male lions tend to have higher levels of testosterone, longer lifespans, and produce more surviving cubs, but hunters also select the same phenotype

(Loveridge et al., 2007). The female and male lions reach maturity around 3 or 4 years, but the male cubs usually start fighting for a pride to reproduce around age 5. The female lions, known as lionesses, have a gestation period of 110 days and produce an average of three cubs (Rudnai, 1973).

Threats One of the largest threat to African lions is from conflict with humans over land use, which leads to habitat loss and is increasing because of demand for agriculture and human settlement (Trinkel and Angelici, 2016). Habitat loss can also lead to prey depletion, an increase in human-wildlife conflict and direct persecution (Breitenmoser and

Breitenmosuer-Wursten, 2016; Figure 3).

Figure 3: Root causes such as human population growth, poverty, and armed conflicts.

There are many effects that contribute to the causes resulting in main problems of reduction in lion range and numbers, and a lack of means and funding. These threats were identified by the 2006 Regional Strategies and CMS 2016 (Breitenmoser and

Breitenmosuer-Wursten, 2016; Figure 3).

With an increase in livestock production, herders are encroaching on lion territories, which may result in human-wildlife conflicts from depredation on livestock. For herders to

prevent depredation, they leave out poisoned meat for the lions to eat and be killed for the safety of their livestock (IUCN, 2014). The chemicals they use are cheaper than replacing an individual, therefore herders find it more rewarding unless they are compensated for their loss. There is evidence that lions and other predators are being systematically targeted when they are in close proximity to livestock.

Between 1970 and 2005, 78 herbivore populations of lion prey species have been closely monitored with resulting in population declines from 52% in Eastern Africa and

85% in Western Africa, but Southern Africa’s herbivore populations have increased by 24%

(Bauer et al., 2016). The West African lion population are now isolated to only confine parts in West Africa and Ethiopia, without any connection to the main African lion species making them more of a risk to extinction (Trinkel and Angelici, 2016).

Other threats to the lion’s population are diseases and illegal trade. Diseases like canine distemper and bovine tuberculosis that is transmitted from domestic animals pose a threat to the African lion populations. Vaccinations for pets and livestock is a must to protect wildlife and stop the spread of diseases (Trinkel and Angelici, 2016). Illegal trade of lion’s body parts such as bones for medicinal purposes pose a threat to the African lion subpopulation (Bauer et al., 2016). China uses the bones to make medicinal wines that was once traditionally used from tiger bones, and there is an increasing interest for the use of lion bones in Asia.

Advantages Protection against Conversion of Land With human population increasing, demand for land development for agriculture and infrastructure is increasing rapidly in developing African countries. Less or no trophy

hunting could result in land conversion from a lack of income and determination to protect the lion’s habitat. The lack of income from trophy hunting would give communities a reason to use the land for other sources of income. Ecotourism may be an alternative, but corrupt areas may have problems getting enough of an income if it is not a safe place to visit. In 1977, Kenya made hunting illegal and now protected areas lack buffer zones, while legal hunting in other countries have hunting blocks to protect the surrounding conservation areas (Lindsey et al., 2013). Hunting blocks are certain areas that are set aside for wildlife trophy hunting. According to Lindsey et al. 2013, the trophy hunting ban in

Kenya has contributed a negative impact on wildlife populations and has failed to help with conservation areas. Without trophy hunting benefits, land protection for the future is unknown and could end up losing its security for development.

Landowners are involved with the revenue of trophy hunting by providing land for hunters to hunt on and wildlife to thrive on. Private and community landowners help the lions by maintaining and restoring wildlife land use, while protecting the lions from illegal poaching. In return, the land and community owners are rewarded with incomes, social benefits to indigenous people and local communities, and jobs (IUCN, 2016). The landowners or communities in charge often negotiate with hunters/hunting organizations and decide who gets the hunting rights on their land. The hunting organizations secure the contracts with the international hunters and runs their hunting trips on private and community land (IUCN, 2016).

Community safety With the decrease in prey populations, lions are looking elsewhere for food, bringing them closer to rural communities (Packer et al., 2006). Lions go after livestock,

which creates a controversy between human and lions. The close encounters are putting human and lions at risk of getting killed. Livestock owners want to protect their land, and communities want to stay safe from being attacked. From 1990-2004, 563 Tanzanians have been killed by African lions and 308 have been injured (Packer et al., 2006). Tanzania has the largest African lion population, but it is also developing country with great demand for agriculture use. Since lions are jeopardizing the livelihoods of communities, this gives people a reason to be against the re-introduction and conservation of the species. People are mostly attacked when they are working on crops during harvest season or while they are sleeping in a hut where the lions force their way in and kill the victim (Packer et al.,

2006). Solutions to move the people away from lion territory was an option in 1992, but with a rapid increase in human population, that is no longer an option in Tanzania (Packer et al., 2006).

Conservation Lindsey et al. (2007) argues that trophy hunting is important in conservation by creating economic incentives to protect land use in areas that are not able to provide revenue from ecotourism. He also argues that trophy hunters will pay more than tourists, meaning less people that are hunters will have less environmental impact. Since the topic of trophy hunting for conservation is a debatable subject, there is a lack of unbiased research to whether or not trophy hunting is the best option for conservation efforts to protect the African lion population. Certain organizations like WWF supports trophy hunting if it benefits wildlife populations by protecting their habitats and ecosystems (Pratt and Hirst, 2017). More research needs to be conducted on how much conservation is actually going to helping the lion’s population in countries that allow trophy hunting. Some

scientists believe that trophy hunting plays a crucial role in wildlife conservation to help communities that are financially limited. Economies do benefit from the high purchased trophy ticket, but when thinking about the lion’s population, certain trophy hunting practices may not be the best option.

Disadvantages Genetic Problems With fragmentation occurring often in the lion’s habitat, many populations are small and may have insufficient genetic variability (Trinkel and Angelici, 2016). Small populations suffer serious genetic problems from inbreeding within just a few generations, but if other populations with genetic variations are connected and not isolated, there is a chance for a decrease in genetic variability (Trinkel et al., 2010). Not only does a small population of lions risk their long term health, but the game of trophy hunting is to kill the largest or most impressive individual, which is usually sexually selected. With hunters going after phenotypes that are preferable for natural selection, it causes potential dangers.

Although there is no evidence of selective removal altering the genetic composition of lion populations, it has occurred with other marine mammals, such as the African elephant

(Loxodonta africana) (Loveridge et al., 2007). African elephants are hunted for their tusks and hunters or poachers often select the largest tusk, resulting in a phenotypic change in their population. Hunting lions can cause increased rates of male infanticide and long-term genetic change in phenotypic traits (Loveridge et al., 2007). When a male leader of a pride is killed, another male will step into the pride and the first thing he does is kill all of the male offspring. He does this because he wants to start new generations that are only his.

This potential infanticide from removing a male leader makes lion populations sensitive to

trophy hunting (Lindsey et al., 2012). If male leaders are removed or males are de- populated in certain areas, cubs are vulnerable to being killed by spotted hyenas (Crocuta crocuta) or other predators because female lions are unable to retain kills (Loveridge et al.,

2007).

Ecological Importance As apex predators, African lions have a very important role in their ecosystem by maintaining herbivore populations. With this regulation, vegetation can thrive and not be overexploited by herbivores. Lion predators are able to kill off vulnerable prey that may spread illnesses or diseases to the prey’s population, resulting in a sharp decline. African lions are keystone species, meaning they help stabilize an entire ecosystem and the removal or depletion of their populations will have cascading negative ecological effects

IUCN, 2014). A predator keystone species can help ecosystems stay more biodiverse by regulating prey species. For example, if there were few lions and their population kept decreasing, while the zebra population was stable and increasing, the zebra population would grow exponentially and diminish vegetation resources for other species. Any imbalance of predator-prey relationships can result in major changes and shifts in the way ecosystems function (Davies et al., 2016).

Cultural Rituals The Maasai culture is a Nilotic ethnic group from central and southern Kenya, and northern Tanzania that have ritual purposes for killing lions. This traditional ritual is a form of a rite of passage. In the Serengeti-Ngorongoro ecosystem in Tanzania, less than 2 lions are killed a year by the Maasai, but trophy harvests equal to about 11.5 per year in this area (Packer et. al., 2011). Another tribe in western Tanzania, called the Sukuma

preform ritual killings, but lion death numbers are unknown. The ritual practices of killing a lion are illegal in Kenya, but retaliatory killing is legal to protect livestock or people from getting killed by lions (Hazzah et al., 2009). Maasai may not always follow rules and regulations with hunting lions, but prosecution can be difficult with individual lions being hunted in isolated areas. Researchers in Tanzania and Kenya have different perspectives on how Maasai hunters are affecting the lion population. Kenya researchers suggest that hunting lions is threatening the population with extinction, while Tanzania researchers claim that unsustainable sport hunting is the largest threat to the lion’s population

(Goldman et al., 2013). Better understanding of the Maasai hunting lions is needed in Kenya and Tanzania, to implement long-term conservation efforts with the tribe. Maasai territories have large concentration of biodiverse wildlife and are known to be intimately connected to beliefs of wild Africa.

Tourism African countries rely strongly on wildlife tourism and Kenya is one of the top countries for it (Buckley and Mossaz, 2017). Since Kenya does not provide trophy hunting incomes to communities, they rely heavily on wildlife tourism. Professional photographers and cinematographers owe fees to Kenya if they want to spot wildlife depending on the party size, it can be 80 to 200 U.S. dollars at present currency for 5-11 people a week

(LawsofKenya, 2009). This only includes having the rights to take photos or film wildlife, and other expenses go into ecotourism such as hotels, flights, and accommodation. Regular tourists also pay these fees to see Africa’s megafauna and expeditions are other cost that benefit local communities with funding and jobs. Conservation efforts through ecotourism is financed by private enterprises, non-government organizations (NGOS), and public

agencies (Buckley and Mossaz, 2017). They raise the funds partially through taxes, NGOs through donations and private enterprises through sales. Cheung (2015) mentions ecotourism is a way to address conservation issues that will provide local stakeholders with socioeconomic benefits. Ecotourism is another way to address human-wildlife conflict with local stakeholders. With ecotourism revenues, it can give communities economic incentives to protect wildlife and to be against retaliatory killings (Cheung, 2015).

Rules and Regulations Kenya Since 1977, Kenya's strict rules and regulation for lion hunting prohibits any hunters from killing lions, but it is legal to kill a lion “if the perpetrator can prove that it was in defense of life or property, including livestock” (Goldman et al., pg. 490, 2013). If this incident was to happen, the person that killed the lion needs to make a report as quick as possible to an officer of the Services (LawsofKenya, 2009). Not only is hunting illegal in

Kenya, but certain body parts of the big five are prohibited to export, including lion skins. If someone causes suffering to a lion without permission of a warden or has possession of one, they will be guilty and liable to fines not exceeding 5,000 shillings (50 U.S. dollars) or imprisonment for no longer than eighteen months, or may be sentenced to both

(LawsofKenya, 2009). Lions are considered a protected animal in Kenya and if hunted, people are liable to fines up to 40,000 shillings (400 U.S. dollars) and/or up to ten years imprisonment (Loc.gov, 2014).

Tanzania Tanzania prohibits trophy hunting inside of the national parks or in certain conservation areas, but outside the barriers of the park, it is legal with a permit issued from

the Director of Wildlife and has to be in specific locations (Goldman et al., 2013; Packer et al., 2011). The type of land used to allow hunters to kill a lion are in game reserves, game controlled, forestry, open and wildlife management areas with a total size of 250,000 square kilometers (61,776,345 acres) (Lindsey et al., 2006; Table 1). Tanzania has age restrictions for trophy hunting with a six year minimum age limit and those who kill a lion from five years old or younger are accepted with penalties (Lindsey et al., 2012; Table 2).

The Tanzania government representatives, an NGO, and scientists have to examine the lion after a hunt to identify the correct age the lion by examining the skull measurements, qualitative assessment of skull, x-rays of the upper pre molar, and other physical features

(Linsey et al., 2012).

Table 1: Edited version of Lindsey et al. (2006) land types used for trophy hunting in

Zimbabwe and Tanzania demonstrating the size (km^2), percent of country that is used for hunting and percent of country used for parks. Both have similar land use for trophy hunting and parks regarding the size of both countries (Lindsey et al., 2006; Table 1).

Table 2: Edited version of Lindsey et al. (2013) Tanzania’s and Zimbabwe’s detailed rules, processes and regulation of managing lion hunting (Lindsey et al., 2013; Table 2).

Zimbabwe Trophy hunting in Zimbabwe is legal inside and outside of park territories.

Zimbabwe has no age restrictions for trophy hunting, but are being considered (Lindsey et al., 2012; Table 2). Scientists found that trophy hunting is affected by corrupt administrative, governance systems, lack of capacity and financing for planning, monitoring, and reporting for adaptive management (Muposhi et al., 2016). The type of land used for hunting in Zimbabwe is private land (46%), state concessions (26%), communal land (22%) and state-owned forestry (6%) with a total size of 64,945 square kilometers (16,048,259 acres) (Lindsey et al., 2006; Table 1).

Imports/Exports of Lion Trophies Through 1996-2006, the country that had the most legal trophy hunting of the

African lion was Tanzania, with exporting an average of 242 trophies per year compared to

Zimbabwe with an average of 96 trophies per year (Brink et al., 2016). From 2004 to 2014, there has been 8,231 imports worldwide of lion trophies and the United States accounts for

77.5% of the imports, including captive animal trophy hunting (Casamitjana and Tsang,

2017; Figure 4). Lions that are considered captive animals for trophy hunting is also referred to as canned hunting, where the lion is kept in a confined area to increase the likelihood of killing it. The trend of worldwide annual trade of African lion hunting trophies has increased and may continue (Figure 4a). Between 2011-2015, international trade of lion trophies have increased by 40.23%, while other species such as the African elephants that are also vulnerable have decreased by 38.31% (Pratt and Hirst, 2017; IUCN, 2017;

Table 3).

(a)

(b)

(c)

Figure 4: a. CITES data of annual worldwide trade of hunting trophies of the African lion shows an increase in overall trade. *CITES data from 2013 and 2014 is incomplete and does not reflect the total number of lion trade between those years. b. African lion third most imported hunting trophies from 2004 to 2014 to the United States. c. African lion most imported hunting trophies that were captive animals from 2004 to 2014 to the United

States (Casamitjana and Tsang, 2017; Figure 4).

Table 3: CITES Trade Database of global trade in trophies by species from 2011-2015. This table illustrates the increasing number of global lion trophy trades, as other decline (Pratt and Hirst, 2017; Table 3).

Case Studies Zimbabwe Case Studies Loveridge et al. (2007) studied the impact of sport-hunting on lion’s populations in

Hwange National Park (HNP), western Zimbabwe. From 1992 to 2002, Zimbabwe has had an annual off-take between 90-141 lions, which is some of the highest in Africa in relation to population size. Over a period of 7 years, 62 lions were tagged in the national park (18 adult male, 10 sub-adult male, 34 adult female) and 24 died during the study from trophy hunting (Loveridge, 2007). Of the 24 lions, 13 were adult males, 5 adult females, and 6 were sub-adult males that have not reached maturity. This means that 60% of the total tagged sub-adult males were killed from hunting. Out of the 62 tagged lions, another 10 lions were killed by natural causes or human-wildlife conflict, with 4 of the females killed from illegal wire snares or gin-traps, 1 adult female by a train, and 5 females from natural causes, while 4 (1 adult male, 1 sub-adult male, 2 adult females) disappeared although intensive searching was occurring (Loveridge, 2007). Another 7 (1 adult male, 3 adult females, 3 sub-adults) unmarked individuals were found diseased within the park by illegal

snares. The mortality rate of the tagged lion’s population within the seven years of the study was 61.29% out of the total 62 lions, including tagged individuals that vanished.

During this study, the team observed or received reports of five incidences of infanticide do to territorial males being removed by sport hunters (Loveridge, 2007). Male mortality from hunters were highest with 72% of tagged lions were killed, resulting in an average of

0.9 males/100km^2, which is 2.5 times higher than average quotas from Tanzania of 0.38 males/100km^2. From 1999-2003, the team found a decline in the adult males to adult females sex ratio, most likely in result from increased male mortality from hunting.

According to Loveridge and the team, “Sport hunting has clear impacts on the demography of the HNP population” (Loveridge et al., pg.556, 2007).

From 2000 to 2012, Loveridge et al. (2016) continued researching effects on lions from trophy hunting in the Hwange National Park in Zimbabwe, where he and his team evaluated 33 prides and 29 male coalitions or singletons. The recorded population consisted of 626 lions that were identified by whisker patterns and other natural features to study births, deaths, immigration and emigration. There were 140 lions (62 adult males,

19 sub adult males, 59 females) that had VHF radio-collars or global positioning system

(GPS) to record their movements and were recorded weekly to bimonthly from a 4x4 vehicle or microlight aircraft (Loveridge et al., 2016). The study was broken up into specific years because of new trophy hunting regulation put in place, which gave the team an advantage to see if there was a change in the lion’s population. When the team started the study in 2000, trophy hunting of both lion genders were hunted immensely, but sub-adults

(<4 years) had the highest proportion of mortality from trophy hunting. This phenomenon occurred until the end of 2004 studies and the team categorized into the “pre-intervention”

period (Loveridge et al., 2016). From 2005 to 2008, the team called this time the

“intervention” period where the Zimbabwe Parks and Wildlife Management Authorities

(ZPWMA) banned trophy hunting throughout the whole country, until it was lifted in 2008.

Studies from 2009-2012 where called the “post-intervention” period, where trophy hunting had better restrictions including only hunting males and within a certain limit pertaining to their population (Loveridge et al., 2016). Loveridge et al. (2016) results demonstrated both lion sexes had higher mortality rates in the “pre-intervention” period than the other two periods (Figure 5). The total number of lions recorded in the study had a positive increase, compared to the pre and post intervention periods. Out of the 62 males that were tagged, 40 died throughout the whole study. Of the total 40 males that died,

68.4% (13 of 19) died in the pre-intervention, 44.4% (12 of 27) in the intervention and

44.4% (15 of 33) in the post-intervention, suggesting that the banning of trophy hunting contributed higher survival rate for the male population (Loveridge et al., pg. 249, 2016;

Figure 5). Of the 59 tagged female lions, 41 of them died with 47% (16 of 34) in the pre- intervention, 34.4% (11 of 32) in the intervention and 48.3% (14 of 29) in the post- intervention (Loveridge et al., pg. 250, 2016; Figure 5). Similar results from the female lion population suggests that a ban on trophy hunting helped regain their population status, but a sharp decline in the post-intervention when male only hunting quotas were introduced leaves questions for further studies. During the 12 years of study, 411 cubs in 25 prides were born with the lowest amount of 118 cubs being during the intervention time

(Loveridge et al., pg. 250, 2016). Although this was the lowest amount of cubs born, the lion population was at its strongest with the intervention of the hunting ban. This study in the national park demonstrated a decline in the lion population suggesting the threat is from

trophy hunting. This area does not face as much threats as other locations because it is in a protected location, showing that an increase for protected areas is a must for the African lion population if trophy hunting is to continue.

Figure 5: Loveridge et al. (2016) demonstrates (A) number of female lion prides showing a steady increase in the intervention, with a trending decrease in post-intervention. (B) number of male coalitions showing an increase in the intervention period, with a steady

rate in the post-intervention. (C) number of individual female lions demonstrating a steep increase of their population after lag from previous hunting regulations in the pre- intervention. (D) number of individual male lions immensely increase in intervention, along with low decline than steady rate. (E) number of sub-adult lions (<4 years) has a decline in the intervention, then a steep increase in post-intervention. (F) total number of lions steeply increase in intervention than steady decline in post-intervention. Error bars account for Standard Deviation (Loveridge et al., 2016; Figure 5).

Tanzania Case Studies Between 1996 and 2008, Packer et al. (2011) analyzed effects of trophy hunting on the lion’s population in Tanzania. They were continuing the work that has be done since

1966, collecting records of individual lions and their populations near 2700km^2 of

Serengeti National Park, also other locations that have been documented including,

2000km^2 near Tarangire National Park studied since 2003, 600-850km^2 of Matambwe

Phototourism Area of Selous Game Reserve studied in 1996 and 1999 and 2007-2008,

250km^2 of Ngorongoro Crater studied since 1963 and estimated density of lions in Katavi

National Park that have been recorded since 1995 (Packer, 2011; Figure 6). Packer and his team distinguished between anthropogenic threats and trophy harvests through specific analytical models. From the long-term studies conducted in the five locations, lion populations decreased in Tarangire, Katavi, and Ngorongoro (Packer, 2011; Figure 6). The

Matambwe lion population stayed a constant rate, while the Serengeti’s lion population increased and both were exposed to moderate levels of trophy hunting (Figure 6).

Serengeti and Ngorongoro lions were exposed to several disease outbreaks that hurt both of their populations, but Serengeti lions were able to recover from diseases (Packer, 2011).

Although the Ngorongoro site is protected from hunting, the populations decreased from continuation of diseases and the Maasai herders. Examples like this, show threats other than trophy hunting can have a negative effect on their population, so considering all impacts are important in analyzing their numbers. Tarangire populations were in a location that exposed them to high threats of retaliatory killing and trophy hunting (Packer et al.,

2011). Katavi’s population also suffered from increased pressures from trophy hunting.

Packer et al. (2011) concluded that Katavi and Tarangire locations were likely affecting the lion’s population and trophy hunting was the primary driver where lion populations decreased. Many threats that the African lions face, including trophy hunting pressures, has shown declines in their populations from Packers study. Low trophy hunting pressures may be acceptable if lion’s population have no other threats.

Figure 6: Packer et al. (2011) study of long-term data on lion populations in (a) Matambwe

Phototourism Area, population steady (b) Serengeti National Park, population increase (c)

Tarangire National Park, population decreased (d) Katavi National Park, population decreased (e) Ngorongoro Crater, population decreased (f) the number of lion attacks on humans throughout the areas studied in Tanzania (solid lines=total population density, dotted lines=adult density, diamonds=annual surveys, and lines without diamonds=continuous observations) (Packer et al., 2011; Figure 6).

Kenya Case Studies Since Kenya has a hunting ban on lions, observing their population may give better understanding to other threats the lions face. Ogutu et al. (2016) studied the lion’s population patterns in the Nakuru Wildlife Conservancy area (NWC) from 1996 to 2015.

Their study consisted of 43 other species that moved in and along the region. The NWC region contains livestock production and wildlife conservation on many land types including privately owned, public, and community shared lands. Nakuru County has a dense human population, which increased by 74% from 1999 to 2009 (Ogutu et al., 2016).

The surrounding areas include agriculture use, developed areas, pastoralism, and cattle ranching. Nakuru County also supports wildlife tourism in three national parks including

Hell’s Gate. Mt. Longonot, and Lake Nakuru. There are current environmental and political problems that threatens most of the species in this region; for instance, intensification of land use, conversion for human use, habitat loss and fragmentation (Ogutu et al., 2016).

These threats are all related to a growing human population in the area (Figure 3). To analyze the lion population, attempted total animal counts were conducted by vehicle every two months in the Lake Nakuru National Park and the Nairobi National Park.

Attempted total animal counts were also performed by aerial in the Masai Mara National

Reserve of Kenya. From all the areas studied through 1996 to 2015, the lion population was increasing, but not significantly (Ogutu et al., 2016; Figure 7). This population analysis covers a wide area of Kenya so it is difficult to pin point the success of their population increase, but it may relate back to bans on trophy hunting. Ogutu et al. (2016) suggests the

NWC has increasing wildlife populations through successful conservation efforts by

landowners collaborating with governmental, international, and non-governmental organizations.

Figure 7: According to Ogutu et al. (2016), Kenya’s lion population trend in the density

(number/km^2) is increasing, but not significantly from 1996 to 2015 for the entire

Nakuru Wildlife Conservancy.

Case Study Comparing Zimbabwe, Tanzania and Kenya’s Lion Population Lindsey et al. (2017) looks at protected areas in different countries including

Tanzania, Zimbabwe and Kenya to understand the importance in sustaining the lion populations at 50% or above and analyzing the main threats in each country. In Kenya, lions occurring at ≥50% carrying capacity were stable or increasing with a higher proportions of protected areas, while serval African countries didn’t have protected areas and the lion populations were decreasing. Lions had higher densities that reached their carrying capacity of ≥50% when the protected areas were fenced, than unfenced (Lindsey et al., 2017). In addition to fenced areas, countries with higher GDP and lower human settlement had higher lions and prey populations. Excessive trophy hunting and protected

areas used primarily for hunting were correlated with an increase in bushmeat poaching and poaching of wildlife for non-meat body parts, relative to protected areas used for tourism (Lindsey et al., 2017). This suggest that hunting pressures contribute to an increase in other threats. Lindsey et al. (2017) calculated the percentage of protected areas threats to lions in 15 different Africa countries, scoring them with “top three threats to lions,” which were bushmeat, human-wildlife conflict and human incursions (pg. 143).

Comparing just Tanzania and Zimbabwe where they both allow trophy hunting, the main threats were in order from human-wildlife conflict, bushmeat to trophy hunting as the third top threat (Table 4). Kenya, Tanzania, and Zimbabwe’s average number of threats were compared with the “top three threats” being human-wildlife conflict (63.2), bushmeat

(39.7) and trophy hunting (25.4) (Lindsey et al., pg. 143, 2017; Table 4a). Accounting for

Kenya’s ban on trophy hunting, it was still the third top threat out of the three countries.

Kenya’s lion population’s main threats are human-wildlife conflict, livestock incursions, and bushmeat. Banning trophy hunting in Kenya may have resulted in more livestock incursions or more agriculture development. Additional studies on this topic are needed to assess the threats to the lion population in protected areas.

Table 4: Edited and calculated version of Lindsey et al. (2017) table of Kenya’s, Tanzania’s, and Zimbabwe’s percentage of protected areas with current threats (a) Kenya, Tanzania and Zimbabwe’s main threats to lions in protected areas are human-wildlife conflict, bushmeat and trophy hunting (b) Tanzania and Zimbabwe’s main threats to lions including human-wildlife conflict (HWF), bushmeat, and trophy hunting (Lindsey et al., 2017; Table

4).

(a)

(b)

Lindsey et al. (2017) provides an estimated status and trend of lion populations with Kenya’s population staying stable, while a majority of Tanzania’s lion population is decreasing (Figure 8). Zimbabwe’s lion population is decreasing in some areas, but has a large portion of the lion population increasing (Figure 8). More studies comparing these sites will give a better understanding to what are the major threats and if trophy hunting contributes to the decline or increase in Zimbabwe’s lion population. Protected areas with few economic or social gains may have pressure to convert the land for human use, if the human population and development continue to increase (Lindsey et al., 2017).

Figure 8: Lindsey et al. (2017) provides an estimated status and trend of lion and prey populations: Kenya’s population is stable, while a majority of Tanzania’s lion population is decreasing. Zimbabwe’s lion population is decreasing in some areas, but has a large portion of the lion population increasing. Countries Kenya (K), Tanzania (T) and Zimbabwe (Z) are marked in the prey population status (Lindsey et al., 2017; Figure 8).

Discussion and Recommendations Kenya’s lion population stayed stable or increased in certain areas since 1996, but are facing threats such as protection against land conversion and humans conflicting with

lions (Lindsey et al., 2017; Ogutu et al., 2016). The case studies suggest that Tanzania’s and

Zimbabwe’s lion populations are effected by trophy hunting, along with other threats such humans conflicting with lions and bushmeat (Lindsey et al., 2017; Loveridge et al., 2007 and 2016; Packer, 2011). Certain areas demonstrated sharp declines in the lion’s population to where strict regulations are needed and lowering other threats if trophy hunting is to continue.

Actions are being taking around the world for the ban on trophy hunting and imports associated with it. In 2013, Botswana banned trophy hunting because of the effects on wildlife populations (Casamitjana and Tsang, 2017). Research on how their population responds long-term is important for identifying if banning trophy hunting is best for their numbers. Certain countries such as Australia and France have banned the imports of lion trophies in 2015 (Casamitjana and Tsang, 2017). States such as New Jersey have also banned imports, exports and sales of parts of all Big Five species.

Outside of the protected areas of NWC in Kenya, many landowners and landholders allow wildlife to compete with their livestock and the government compensates them for their losses through the Wildlife Conservation and Management Act that was passed in

2013 (Ogutu et al., 2016). The Act protects and advocates for the protection of wildlife by creating policies where human-wildlife co-exist without conflict. Ogutu et al. (2016) suggests that by conserving and protecting wildlife habitats, landowners can help increase the amount of protected areas for wildlife and decrease the amount of human-wildlife conflict, which was the highest threat to lions, according to Lindsey et al. (2017) (Table 4).

“According to the Kenya Wildlife Conservancies Association (KWCA), 177 communal and

private wildlife conservancies covering 62,281 km^2 or 10.71% of Kenya’s land surface had been formed by 2016 and benefit about 700,000 people nationally” (Ogutu et al., pg.

25, 2016). Protection against human-wildlife conflict (HWS) may be the best solution if trophy hunting were to continue to sustain the lion population, since HWC is the biggest threat within the three countries (Lindsey et al., 2017; Table 4).

In 2007, a conservation organization called the Lion Guardians wanted to find long- term solutions for lions and people to coexist in the same area by using cultural values, community participation and science (Goldman et al, 2013). The Maasai are heavily involved with this organization with it providing jobs and incomes to the communities. In return, the Maasai work by tracking lion’s movements, educating communities, deterring lion hunts and improving husbandry techniques. It is important for Maasai people to track lions to stop illegal lion hunting and to provide scientists with population estimates.

Specifically identifying and hunting mature nomads that may take over a strong pride leader may increase the lion cubs chances for survival and in turn increase the lions population overall, but associating specific nomads may be a challenge. Hunting specific lions that have reached their sexual maturity and have had many successful litters may also be an alternative, then picking out a young male.

Monitoring the age of specific trophies to be over a minimum requirement for lion’s to reach maturity and reproduce may have more breeding success (Loveridge et al., 2007).

Packer et al. (2011) suggests that harvesting males need to have age restrictions on ≥ 5 years old to minimize effects on their population from trophy hunting. Similar age requirements should be met for every population in Africa. Penalties need to be in place

and pursued more frequently if harvesting of lions below the required age is performed. “A strict age minimum would help ensure safe harvest levels despite uncertainties about local population sizes” (Packer et al., pg. 151, 2011). Brink et al. (2016) recommends from recent studies in Zambia a minimum age requirement of at least seven years, with periods of no trophy hunting or periods of recovery for trophy hunting to be sustainable. There are other alternatives to hunting lions, such as hunting a species that is not under threat. Hunting a different animal for a certain amount of time may give the lion population a boost, and more scientific data could be collected to analyze how lions are coping with other threats they face.

Certain quotas within specific areas for trophy hunting may help regulate the amount of hunting within a lion population can occur before it effects their numbers. In Tanzania, researcher suggest that sustainable lion trophy hunting quotas should be one lion per

1000km^2 for Selous Game Reserve and 0.5 lion per 1000km^2 for the rest of Tanzania

(Brink et al., 2016; Packer et al., 2011). In 2007, Tanzania’s average hunting quota was 0.38 males per 100km^2, which is much lower than in Zimbabwe with 0.9 males per 100km^2

(Loveridge, 2007). Loveridge et al. (2007) recommends a reduction of quotas to no more than hunting 10% of adult males in a population, depending on their current status and other threats contributing to their decline.

Conclusion Trophy hunting has made a negative impact on the lion populations in Tanzania and

Zimbabwe. African lion population’s main threats such as human-wildlife conflict need to be recognized and considered when determining trophy hunting rules and regulations.

Landowners and communities need to work with the government on how to solve the

human-wildlife conflict that is effecting their population. Protection against habitat loss is crucial and can be established by creating more tourism parks or reserves, so land conversion will occur less and there could be potential for sustainable economic growth.

Creel et al. (2016) mentioned trophy hunting is easier to assess than other threats to the

African lion population, which is something scientists should pay close attention to when analyzing threats to their population. By examining lion prey populations, scientists will get a better understanding if they are subject to lack of resources. Trophy hunting for lion conservation is controversial, but dense research is needed to identify just how beneficial and how much money is going directly towards helping the lion’s population. Overall, trophy hunting decreases lion populations in Tanzania and Zimbabwe, so an increase in protected areas with hunting bans enforced may help increase or stabilize the African lion’s population.

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