Population status of leopard in one of Africa’s largest wilderness areas and the challenge of monitoring at scale

Remarkably little is still understood about how the leopard (Panthera
pardus) is faring in much of its remaining African range, despite the
species’ importance for ecosystem function and generating funding for
conservation via tourism. In this study, we address this knowledge gap in
southern Tanzania’s Selous-Nyerere ecosystem, one of the largest intact
wilderness areas on the continent, by estimating leopard population
density via spatially explicit capture-recapture (SECR) modelling of data
from seven camera trap surveys. Population density was highest in Nyerere
National Park’s Matambwe sector (8.08 ± SE 1.54 adult and subadult
leopards per 100 km2), followed by Selous Game Reserve’s Miguruwe sector
(7.38 ± 1.26 per 100 km2); Nyerere NP’s Msolwa sector (6.05 ± 0.78 per 100
km2); Selous GR’s Liwale sector (5.93 ± 0.88 per 100 km2), western
Kingupira sector (5.58 ± 0.87 per 100 km2), and eastern Kingupira sector
(5.22 ± 0.71 per 100 km2); and Nyerere NP’s Kalulu sector (3.80 ± 0.64 per
100 km2). Together, our surveys covered an important component of extant
leopard range in Tanzania, and our findings highlight the importance of
the Selous-Nyerere ecosystem as a leopard stronghold. The estimates
include the highest leopard densities yet documented in miombo woodland,
which represents nearly one fifth of the species’ remaining African range.
Unlike lion, leopard population density was highly correlated with
relative abundance of preferred prey. Although limited by a small number
of data points, this suggests that the two species may not be uniformly
affected by anthropogenic threats. Threats to leopard in Selous-Nyerere
include accelerating habitat conversion in boundary areas and bushmeat
poaching, which impacts leopard indirectly by suppressing prey populations
and directly via accidental snaring. Practical implication: Placed in the
context of range-wide leopard monitoring, this study highlights the need
to address persistent knowledge gaps on the species’ continental status
and prioritise sites for monitoring based on their potential to inform
evidence-based conservation management.

尽管豹（Panthera pardus）对生态系统功能至关重要，且可通过旅游业为保护工作募集资金，但目前学界对其现存非洲分布区内绝大多数区域的种群存续现状仍知之甚少。本研究聚焦坦桑尼亚南部的塞卢斯-恩耶雷生态系统——这片区域是非洲大陆现存规模最大的完整荒野之一，通过对7次红外相机陷阱（camera trap）调查的数据开展空间显式捕获-再捕获（SECR）建模，以此估算豹的种群密度，填补这一认知空白。研究测得的种群密度最高值出现在恩耶雷国家公园的马坦布韦片区（每100平方公里成年及亚成年豹8.08±标准误1.54只），其次依次为塞卢斯禁猎区的米古鲁韦片区（7.38±1.26只/100km²）、恩耶雷国家公园的姆索卢瓦片区（6.05±0.78只/100km²）、塞卢斯禁猎区的利瓦莱片区（5.93±0.88只/100km²）、西部金古皮拉片区（5.58±0.87只/100km²）与东部金古皮拉片区（5.22±0.71只/100km²），最低值为恩耶雷国家公园的卡卢卢片区（3.80±0.64只/100km²）。本次调查覆盖了坦桑尼亚境内现存豹分布区的重要组成部分，研究结果凸显了塞卢斯-恩耶雷生态系统作为豹种群庇护所的核心价值。本次估算的种群密度，是目前米奥姆博林地（miombo woodland）中已记录到的最高豹密度，而米奥姆博林地约占该物种现存非洲分布区的五分之一。与狮子不同，豹的种群密度与其偏好猎物的相对丰度呈高度正相关。尽管本研究受限于数据点数量较少，但该结果提示，人类活动威胁对这两个物种种群的影响并不具有统一性。塞卢斯-恩耶雷生态系统中豹面临的主要威胁包括边界区域不断加剧的生境破坏与转换，以及丛林肉偷猎：偷猎行为一方面通过压制猎物种群间接制约豹的生存，另一方面也会导致豹意外落入捕兽套而直接死亡。结合全球范围的豹监测工作语境来看，本研究凸显了填补该物种大陆级种群状况认知空白的迫切性，并提出应依据各监测点为循证保护管理提供决策支持的潜力，优先划定监测重点区域。