An analysis of threats,strategies, and opportunities for African rhinoceros conservation

The complexity and magnitude of threats to black (Diceros bicornis) and white (Ceratotherium simum) rhinoceros conservation in Africa have triggered global concerns and actions. In this study, we analyzed (i) threats to rhinoceros conservation including external shocks, (ii) historical rhinoceros conservation strategies in Zimbabwe and Africa, more broadly, and (iii) opportunities for enhanced rhinoceros conservation in Zimbabwe and Africa. A literature search from 1975 to 2020 was carried out using a predefined search protocol, involving a number of filters based on a set of keywords to balance search sensitivity with specificity. A total of 193 articles, which were most relevant to key themes on rhinoceros conservation, were used in this study. The common threats to rhinoceros conservation identified in this paper include poaching, habitat fragmentation and loss, international trade in illegal rhino products, and external shocks such as global financial recessions and pandemics. Cascading effects emanating from these threats include small and isolated populations, which are prone to genetic, demographic, and environmental uncertainties. Rhinoceros conservation strategies being implemented include education and awareness campaigns, better equipped and more antipoaching efforts, use of innovative systems and technologies, dehorning, and enhancing safety nets, and livelihoods of local communities. Opportunities for rhinoceros conservation vary across the spatial scale, and these include (a) a well‐coordinated stakeholder and community involvement, (b) strategic meta‐population management, (c) enhancing law enforcement initiatives through incorporating real‐time surveillance technologies and intruder detection sensor networks for crime detection, (d) scaling up demand reduction awareness campaigns, and (e) developing more certified wildlife crime and forensic laboratories, and information repository for international corporation.     

How does poaching affect the size of national parks?

A variety of human activities have detrimental impacts on populations of species the park is designed to protect. These impacts range from direct hunting for trophy or subsistence needs, through vehicular collisions, to the direct loss of habitat due to forestry and agricultural activity. These impacts reduce the effective size of the parks and require changes in management policy that deal both with the direct cause of the problem and the underlying social conflicts that the presence of parks can place on humans in the surrounding communities. Recent studies from the Serengeti illustrate that increases in anti-poaching patrols increase the risk of poacher detection and lead to dramatic declines in levels of poaching. The economic arguments that support investment in anti-poaching patrols, rather than increased sentences for poachers who are caught, can be generalized to examine the costs and benefits of other changes in natural resource management that arise when attempting to manage the impact of anthropogenic activities in and around national parks.     

Disruption of Rhino Demography by Poachers May Lead to Population Declines in Kruger National Park,South Africa

The onslaught on the World’s rhinoceroses continues despite numerous initiatives aimed at curbing it. When losses due to poaching exceed birth rates, declining rhino populations result. We used previously published estimates and growth rates for black rhinos (2008) and white rhinos (2010) together with known poaching trends at the time to predict population sizes and poaching rates in Kruger National Park, South Africa for 2013. Kruger is a stronghold for the south-eastern black rhino and southern white rhino. Counting rhinos on 878 blocks 3x3 km in size using helicopters, estimating availability bias and collating observer and detectability biases allowed estimates using the Jolly’s estimator. The exponential escalation in number of rhinos poached per day appears to have slowed. The black rhino estimate of 414 individuals (95% confidence interval: 343-487) was lower than the predicted 835 individuals (95% CI: 754-956). The white rhino estimate of 8,968 individuals (95% CI: 8,394-9,564) overlapped with the predicted 9,417 individuals (95% CI: 7,698-11,183). Density- and rainfall-dependent responses in birth- and death rates of white rhinos provide opportunities to offset anticipated poaching effects through removals of rhinos from high density areas to increase birth and survival rates. Biological management of rhinos, however, need complimentary management of the poaching threat as present poaching trends predict detectable declines in white rhino abundances by 2018. Strategic responses such as anti-poaching that protect supply from illegal harvesting, reducing demand, and increasing supply commonly require crime network disruption as a first step complimented by providing options for alternative economies in areas abutting protected areas.     

A security game approach for strategic conservation against poaching considering food web complexities

Mitigating the poaching pressure on food webs under multiple constraints (including financial and ecological ones) remains an open problem within conservation. Within this field, mathematically modeling the effects of poaching threats on managerial decision-making is a novel approach. To fill this scientific gap, the present paper uses a security game approach to model the interactions between an environmental manager (defender) and a group of profit-seeking pursuit poachers (attackers) who target species which are nodes of the food web. Based upon the non-cooperative Stackelberg game, the objective of the defender (as leader) is to keep the food web at or near equilibrium through optimally manipulating the populations of an optimal subset of species. In contrast, each attacker strives to maximize monetary profit by hunting an optimal population size of the selected species. The model is validated by a numerical example examining the food web of the endangered Persian leopard (Panthera pardus saxicolor), which lives in Golestan National Park (GNP), Iran. The model provides an overarching biotic intervention strategy to keep the (1 predator-4 prey) food web near equilibrium, while only 2 prey species (the urial (Ovis vignei) and the red deer (Cervus elaphus)) are directly threatened by poachers. The examination revealed that both species population data and poaching data should be taken into account to set effective multi-species conservation prioritization levels. In a sensitivity analysis approach, it was found that, despite the fact that red deer is endangered and preferred by poachers, the deterrent penalty measure should be 1.5 times greater for poaching urial than red deer. The output analysis illustrated that, in order to bring the urial deterrent penalty measure closer to the red deer one, enforcement measures should be about 2.5 times stricter for poaching urial than red deer. The results specifically yield insight into how to optimally conserve a food web equilibrium under poaching pressure and within several constraints.     

Anthropogenic Influences on Conservation Values of White Rhinoceros

White rhinoceros (rhinos) is a keystone conservation species and also provides revenue for protection agencies. Restoring or mimicking the outcomes of impeded ecological processes allows reconciliation of biodiversity and financial objectives. We evaluate the consequences of white rhino management removal, and in recent times, poaching, on population persistence, regional conservation outcomes and opportunities for revenue generation. In Kruger National Park, white rhinos increased from 1998 to 2008. Since then the population may vary non-directionally. In 2010, we estimated 10,621 (95% CI: 8,767–12,682) white rhinos using three different population estimation methods. The desired management effect of a varying population was detectable after 2008. Age and sex structures in sink areas (focal rhino capture areas) were different from elsewhere. This comes from relatively more sub-adults being removed by managers than what the standing age distribution defined. Poachers in turn focused on more adults in 2011. Although the effect of poaching was not detectable at the population level given the confidence intervals of estimates, managers accommodated expected poaching annually and adapted management removals. The present poaching trend predicts that 432 white rhinos may be poached in Kruger during 2012. The white rhino management model mimicking outcomes of impeded ecological processes predicts 397 rhino management removals are required. At present poachers may be doing “management removals,” but conservationists have no opportunity left to contribute to regional rhino conservation strategies or generate revenue through white rhino sales. In addition, continued trends in poaching predict detectable white rhino declines in Kruger National Park by 2016. Our results suggest that conservationists need innovative approaches that reduce financial incentives to curb the threats that poaching poses to several conservation values of natural resources such as white rhinos.     

Monitoring Great Ape and Elephant Abundance at Large Spatial Scales: Measuring Effectiveness of a Conservation Landscape

Protected areas are fundamental to biodiversity conservation, but there is growing recognition of the need to extend beyond protected areas to meet the ecological requirements of species at larger scales. Landscape-scale conservation requires an evaluation of management impact on biodiversity under different land-use strategies; this is challenging and there exist few empirical studies. In a conservation landscape in northern Republic of Congo we demonstrate the application of a large-scale monitoring program designed to evaluate the impact of conservation interventions on three globally threatened species: western gorillas, chimpanzees and forest elephants, under three land-use types: integral protection, commercial logging, and community-based natural resource management. We applied distance-sampling methods to examine species abundance across different land-use types under varying degrees of management and human disturbance. We found no clear trends in abundance between land-use types. However, units with interventions designed to reduce poaching and protect habitats - irrespective of land-use type - harboured all three species at consistently higher abundance than a neighbouring logging concession undergoing no wildlife management. We applied Generalized-Additive Models to evaluate a priori predictions of species response to different landscape processes. Our results indicate that, given adequate protection from poaching, elephants and gorillas can profit from herbaceous vegetation in recently logged forests and maintain access to ecologically important resources located outside of protected areas. However, proximity to the single integrally protected area in the landscape maintained an overriding positive influence on elephant abundance, and logging roads – even subject to anti-poaching controls - were exploited by elephant poachers and had a major negative influence on elephant distribution. Chimpanzees show a clear preference for unlogged or more mature forests and human disturbance had a negative influence on chimpanzee abundance, in spite of anti-poaching interventions. We caution against the pitfalls of missing and confounded co-variables in model-based estimation approaches and highlight the importance of spatial scale in the response of different species to landscape processes. We stress the importance of a stratified design-based approach to monitoring species status in response to conservation interventions and advocate a holistic framework for landscape-scale monitoring that includes smaller-scale targeted research and punctual assessment of threats.     

The pattern of poaching signs in Ugalla Game Reserve,western Tanzania

Illegal harvesting of wildlife resources is an important challenge facing protected areas in Africa. A better understanding of its nature would improve the way in which it is managed. We investigated the degree of poaching into different types of natural resources and its management implications in Ugalla Game Reserve, western Tanzania, using data on spatial distribution of poaching signs. Poaching signs were distributed nonrandomly through the reserve, which suggested that poachers targeted particular resources at certain areas of the reserve. Logging was the predominant illegal activity, followed by bushmeat hunting and illegal fishing. Logging signs were widespread at Ugalla east and Ugalla south. The latter also contained the highest encounter rate of bushmeat signs. Illegal fishing was extensive around the main rivers in the reserve. For improved conservation enforcement in western Tanzania and similar ecosystems, conservation efforts should take into consideration the distribution and composition of different types of poaching.     

Development of a Monoclonal Antibody Detection Assay for Species-Specific Identification of Abalone

Species identification based on biochemical and molecular techniques has a broad range of applications. These include compliance enforcement, the management and conservation of marine organisms, and commercial quality control. Abalone poaching worldwide and illegal trade in abalone products have increased mainly because of the attractive prices obtained and caused a sharp decline in stocks. Alleged poachers have been acquitted because of lack of evidence to correctly identify species. Therefore, a robust method is required that would identify tissue of abalone origin to species level. The aim of this study was to develop immunologic techniques, using monoclonal and polyclonal antibodies, to identify 10 different abalone species and subspecies from South Africa, the United States, Australia, and Japan. The combination of 3 developed monoclonal antibodies to South African abalone (Haliotis midae) enabled differentiation between most of the 10 species including the subspecies H. diversicolor supertexta and H. diversicolor diversicolor. In a novel approach, using antibodies of patients with allergy to abalone, the differentiation of additional subspecies, H. discus discus and H. discus hannai, was possible. A field-based immunoassay was developed to identify confiscated tissue of abalone origin.     

Forage patch use by grazing herbivores in a South African grazing ecosystem

Understanding how different herbivores make forage patch use choices explains how they maintain an adequate nutritional status, which is important for effective conservation management of grazing ecosystems. Using telemetry data, we investigated nonruminant zebra (Equus burchelli) and ruminant red hartebeest (Alcelaphus buselaphus subspecies camaa), use of burnt patches in a landscape mosaic of nutrient-poor, old grassland interspersed with young, recently burnt, nutrient-rich grass patches. The Mkambati Nature Reserve landscape on the east coast of South Africa provided large grazers with a challenge in finding and using appropriate patches in which to forage to meet their nutritional requirements. In Mkambati, grassland fires, mostly ignited by poachers, induce regrowth of young nutrient-rich grass, which subsequently attract grazers. We tested if the study animals foraged more in burnt patches than in the unburned grassland and whether burnt patch use was related to the distance to the previously visited burnt patch, burnt patch size, burnt patch age, and distance to areas with high poaching risk using MANOVA. In general, zebra moved faster than red hartebeest, and both species moved faster in unburnt grassland than in burnt patches. Red hartebeest and zebra patch selection were influenced by interpatch distance, patch age, patch size, and poaching risk. A limited set of intrinsic traits, i.e., body mass, digestion strategy, and muzzle width, yielded different patch use rules for the two species. Large ungulates patch use behaviour varied among species and across conditions and was influenced by anthropogenic impacts such as poaching and changed fire regimes. This could potentially affect biodiversity negatively and needs to be factored into management of conservation areas.     

Inferring wildlife poaching in southeast Asia with multispecies dynamic occupancy models

Determining the ‘space race’ between co-occurring species is crucial to understand the effects of interspecific interactions on the extinction risk of species threatened by poachers and predators. Dynamic two-species occupancy models provide a flexible framework to decompose complex species interaction patterns, while accounting for imperfect detection. These models can describe poachers–wildlife interactions, as they allow estimating occupancy, extinction and colonisation probabilities of wildlife conditional on the occurrence of poachers and vice versa. We applied our model to a case study on wildlife poaching in the eastern plains of Cambodia. We used co-occurrence data extracted from the database of the SMART partnership to study the distribution dynamics between poachers and six ungulate species pooled together into the tiger prey guild. We used four years of survey data reporting the locations of snares and of presence signs of the ungulates recorded by rangers during their monthly multi-patrolling sessions. Our results showed that a substantial proportion of the sites occupied by ungulate species went extinct over the years of the study while the proportion of sites colonised by poachers increased. We also showed, for the first time, that spatio-temporal heterogeneity in the patrolling effort explains a great deal of the variation in the detection of poachers and ungulates. Our approach provides practitioners with a flexible and robust tool to assess conservation status of species and extinction risk of wildlife populations. It can assist managers in better evaluating, learning and adapting the patrolling strategies of rangers.     

Global trends and factors associated with the illegal killing of elephants: A hierarchical bayesian analysis of carcass encounter data

Elephant poaching and the ivory trade remain high on the agenda at meetings of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Well-informed debates require robust estimates of trends, the spatial distribution of poaching, and drivers of poaching. We present an analysis of trends and drivers of an indicator of elephant poaching of all elephant species. The site-based monitoring system known as Monitoring the Illegal Killing of Elephants (MIKE), set up by the 10(th) Conference of the Parties of CITES in 1997, produces carcass encounter data reported mainly by anti-poaching patrols. Data analyzed were site by year totals of 6,337 carcasses from 66 sites in Africa and Asia from 2002-2009. Analysis of these observational data is a serious challenge to traditional statistical methods because of the opportunistic and non-random nature of patrols, and the heterogeneity across sites. Adopting a bayesian hierarchical modeling approach, we used the proportion of carcasses that were illegally killed (PIKE) as a poaching index, to estimate the trend and the effects of site- and country-level factors associated with poaching. Important drivers of illegal killing that emerged at country level were poor governance and low levels of human development, and at site level, forest cover and area of the site in regions where human population density is low. After a drop from 2002, PIKE remained fairly constant from 2003 until 2006, after which it increased until 2008. The results for 2009 indicate a decline. Sites with PIKE ranging from the lowest to the highest were identified. The results of the analysis provide a sound information base for scientific evidence-based decision making in the CITES process.     

Field study on the choice of friends in two multi-racial pre-schools (South Africa/London)

The present research examined the influence of the two independent variables sex and race on the choice of friends in pre-school children. Data for this investigation were collected in two pre-schools, one situated in Stellenbosch, South Africa, the other in London, U.K. Both schools have in common that they accommodate children of different racial backgrounds (black, white, and coloured children), but the children's experience with desegregated classrooms differ. Friendship was operational defined with thirteen categories, summarized to the basic category pro-social behaviour. Fifty hours of free-play time were taped with one video camera in South Africa, and hundred hours were taped with two video cameras in London. The results showed that sex and race interact in their effect on the choice of friends. In South Africa race is supposed to be a strong indicator for friendship choices, especially for black children, whereas the black children in London choose friends more or less on the basis of sex.     

Evaluating determinants of wire-snare poaching risk in the Boland Mountain Complex of South Africa

Wire-snare poaching for bushmeat is increasingly recognised as a global threat to biodiversity and is directly linked to the reduction or extirpation of targeted species, threatened species bycatch and the loss of functional ecosystem processes. However, studies evaluating the extent and underlying dynamics of bushmeat poaching in southern Africa remain limited. Despite growing evidence of wire-snaring incidence in the Boland Mountain Complex of South Africa, formal research has been restricted to unverified reporting. Through systematic anti-poaching patrols on private agricultural properties bordering protected areas, this study characterised snaring, compared interview- and patrol-reported incidence to quantify the influence of socioeconomic and biophysical determinants of bushmeat poaching, and spatially predicted poaching risk throughout the region. In total, 671 snares were located during 96 (46%) bi-annual patrols (June 2019 to June 2020), covering a total distance of 1,332 km across 112 private properties. Of these snares, 537 (80%) were anchored and active. Furthermore, snares were primarily positioned along game trails (47%) and fence lines (39%) where they were predominantly anchored to trees (40%) or fence posts (39%). Snares were mainly made of wire (70%) or nylon (19%) and suspended at 0–60 cm (97%). Snaring incidence did not differ significantly (P = 0.186) between interviews (n = 307) and patrols (n = 180), reporting on average 2.32 ± 0.23 (SE) snares on the property in the month preceding each interview and 3.34 ± 0.55 snares removed on interviewed properties (n = 92). Interview-reported snaring positively correlated with the number of resident families per property and the use of lethal control measures but was negatively correlated with owners endorsing punitive measures and where orchards were the primary agricultural output. In contrast, patrol-reported snaring frequency increased with the number of resident families per property, farmer residency and a primary agricultural output of orchards. High risk areas for snaring were predicted between 2.2 and 5.8 km from the nearest public street, between 1.5 and 2.2 km from the nearest settlement, at elevations of 300–500 m, between 1.8 and 2.5 km from the nearest protected area and 0.5–3.2 km from the nearest river, thus identifying new poaching hotspots across the region. This study features a novel interdisciplinary approach to understanding the complex nature of bushmeat poaching and adds applied conservation value by optimising current monitoring and law enforcement efforts.     

Poaching lowers elephant path tortuosity: implications for conservation

Poaching is the most immediate threat to African elephants (Loxodonta africana). Several continental-wide surges in poaching have occurred since the latter half of the twentieth century, and the latest surge occurred from 2007 to 2012. The behavioral responses of elephants to poaching risk has not been studied widely because of a lack of high-resolution movement data collected simultaneously with verified causes of mortality. We managed to collate 2 such datasets from 2004 to 2013. We studied the spatial-temporal changes in movement behavior of 11 elephants in their core areas. Past studies have focused on elephant movement along corridors. We tested for the effect of poaching risk on their path straightness (i.e., tortuosity) while controlling for other environmental and human activities in the landscape using a set of generalized linear mixed models. To test for temporal variation of tortuosity, we used a time-series linear model. Elephants turned less frequently while they were in poaching locations and at times with a high level of poaching activity, even though their speed did not change. The variation of tortuosity is a good indicator of differences in poaching risk as perceived by the elephants, which could complement patrol-based anti-poaching efforts by wildlife managers, especially in remote, inaccessible landscapes. © 2019 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society     

Daily activity patterns and habitat use of the lowland tapir (Tapirus terrestris) in the Atlantic Forest

We studied the daily activity pattern and habitat use of the lowland tapir Tapirus terrestris and their relationship with environmental and anthropic variables. We used photographic records of tapirs obtained during five camera-trap surveys conducted in three areas of the Atlantic Forest of Argentina that differ in their protection against poaching. The daily activity pattern was analyzed with circular statistics and linear regression. The effect of protection against poaching and environmental variables on habitat use of tapirs was analyzed using occupancy modeling. Tapirs were nocturnal all year round, with 89% of the records between 1800 h and 0700 h. The proportion of nocturnal records and the recording rate did not change with mean daily temperature. The daily activity pattern of tapirs was not affected by the sex of the individuals, the lunar cycle or the protection level of the area. The probability of detecting tapirs increased with the distance to the nearest access points for poachers and decreased with the abundance of bamboo in the understory and increasing trail width. The probability of use of an area by tapirs increased with increasing protection against poaching and distance to the nearest access points for poachers. These results suggest that poaching is one of the factors with significant effect on habitat use by tapirs but not on their daily activity patterns.     

The political culture of poaching: a case study from northern Greece

Poaching has deep social and cultural roots and its meanings are multi-layered. This article explores the meanings attached to the practice of illegal hunting and fishing around Lake Kerkini in northern Greece. Here poaching must be considered in the context of a disordered ecosystem, where the dominance of locally maligned fish and bird species results from economic and environmental policy designed to benefit distant farmers. We conclude that poaching cannot be understood only as an individual action, but as one where collective and personal identities are defended in the face of seemingly irrevocable economic and social decline. The discussion shows that poachers identify different kinds of poaching. Some of the most apparent forms of poaching, done by local inhabitants, may be less damaging than other commercially oriented forms, including by outsiders. Poaching is motivated through a complex mix of factors. Our data lead us to discuss two manifestations of poaching (a) poaching as a form of collective resistance; and (b) poaching as a violation of culturally valued types of human-nature interaction. Some people who admit undertaking what they perceive as least detrimental forms of poaching are antagonistic towards what they construe to be truly harmful forms. Such people appear willing to act and to support actions against types of poaching they agree to be threatening. This is a message with potential importance for environmental management strategy.     

Shoot, shovel and shut up: cryptic poaching slows restoration of a large carnivore in Europe

Poaching is a widespread and well-appreciated problem for the conservation of many threatened species. Because poaching is illegal, there is strong incentive for poachers to conceal their activities, and consequently, little data on the effects of poaching on population dynamics are available. Quantifying poaching mortality should be a required knowledge when developing conservation plans for endangered species but is hampered by methodological challenges. We show that rigorous estimates of the effects of poaching relative to other sources of mortality can be obtained with a hierarchical state-space model combined with multiple sources of data. Using the Scandinavian wolf (Canis lupus) population as an illustrative example, we show that poaching accounted for approximately half of total mortality and more than two-thirds of total poaching remained undetected by conventional methods, a source of mortality we term as 'cryptic poaching'. Our simulations suggest that without poaching during the past decade, the population would have been almost four times as large in 2009. Such a severe impact of poaching on population recovery may be widespread among large carnivores. We believe that conservation strategies for large carnivores considering only observed data may not be adequate and should be revised by including and quantifying cryptic poaching.     

Tourists' Effects on Drivers of Working Asian Elephants

ABSTRACT

A growing wildlife tourist industry in Asia sometimes includes the use of elephants to transport tourists. Elephant drivers are responsible for the safe management of their elephants while loading, transporting, and unloading tourists for rides to view wildlife. This study sought to investigate the preferences and perceptions of elephant drivers regarding tourists when viewing rhinoceroses in the field. Drivers were interviewed with standardized questions with translator assistance and asked to show the distances from the rhinoceros at which both they and tourists preferred to view a rhinoceros. According to drivers, they preferred to be a longer distance from a rhinoceros than did tourists. Drivers described that some tourists wanted to get closer than was safe to rhinoceroses and other wildlife so as to take good photographs; some even wanted to be within touching distance. Drivers noted that tourists with long camera lenses did not seek or request to be as close to the rhinoceros as tourists with cameras with short lenses.     

Genetic structure of the black rhinoceros (Diceros bicornis) in south-eastern Africa

Despite an on-going struggle to conserve the endangered black rhinoceros (Diceros bicornis) since the 1980s, huge capital investment and several genetic surveys, the level of genetic structure and connectivity among populations in southern Africa is not well understood. Here, we undertake a major population genetic study of black rhinoceros in the Zimbabwe Lowveld, an area inhabited by over half of that country’s original Zambezi descendants plus one large population sourced from the relict KwaZulu stock of South Africa. Using nuclear microsatellite and mitochondrial DNA data, we found much higher levels of genetic diversity in the indigenous Zimbabwean populations, where observed multilocus heterozygosity was 0.54 versus 0.40 in KwaZulu, and maternal haplotype diversity was 0.77 versus 0.03. We show, for the first time, that both gene pools can be differentiated from each other on the basis of nuclear markers. This, along with the discovery of recent gene flow between all Lowveld populations, suggests that Zimbabwean and South African gene pools were prehistorically connected.     

Will tree euphorbias (Euphorbia tetragona and Euphorbia triangularis) survive under the impact of black rhinoceros (Bicornis diceros minor) browsing in the Great Fish River Reserve,South Africa?

The impact of black rhinoceros (Bicornis diceros minor) on the tree euphorbias Euphorbia tetragona and Euphorbia triangularis was studied in the Great Fish River Reserve, South Africa. Black rhinoceros pushed over about 5–7% of the trees in a 2‐month period. There was a preference of rhinos for smaller trees, however this preference did not guarantee euphorbia survival in the larger size classes. This means that tree euphorbias could very well disappear from all areas accessible to rhinos. Rhino feeding choices were correlated with higher plant moisture content, higher nitrogen content, and a higher digestibility.