The gopher tortoise (Gopherus polyphemus) is a burrowing tortoise endemic to the sandy uplands of the southeastern United States Coastal Plain, and its range spans from eastern Louisiana to southwestern South Carolina to southern Florida. It occurs in a variety of forest types, but perhaps no ecosystem has a closer biological and cultural association with the species than the longleaf pine (Pinus palustris)—wiregrass (Aristida spp.) ecosystem. The ecosystem evolved with frequent ground fire, which maintained relatively open forest canopy conditions and abundant light on the forest floor to meet the tortoise's foraging and thermoregulatory needs. The gopher tortoise was once widespread and common, but with reduction of the longleaf pine forest following European settlement, active fire suppression, and unsustainable harvesting of adult tortoises, the gopher tortoise population sharply declined to the point that it is currently under assessment for listing under the United States Endangered Species Act.

The tortoise is a charismatic species whose presence within a landscape is often given away by its conspicuous burrows and bright sand aprons. Tortoises have characteristics that have made them a historically appealing subject for capture and marking. Tortoises are relatively easy to catch (with sufficient patience) and handle, their longevity and high site fidelity produce a good chance of later re‐encounter, and tortoise carapaces can be marked inexpensively and durably. The first known use of marked tortoises for scientific study was that of Goin and Goff (1941), who reported 1‐year growth increments of tortoises in central Florida.

Awareness of an emerging conservation plight for the species led to population studies starting in the late 1970s and early 1980s. Studies in southwest Georgia (McRae et al. 1981) and northcentral Florida (Diemer 1992) demonstrated the utility of mark‐recapture methods for understanding tortoise movements and population age structure; more mark‐recapture studies followed by other researchers at other sites. At about the same time, an acceleration in Florida of large‐scale translocations of groups of tortoises from sites slated for development resulted in the release of permanently marked animals into recipient sites (Ashton and Burke 2007, Cozad et al. 2020). Thus, the number of sites hosting populations of marked tortoises—including living individuals marked decades ago—has steadily increased even as habitats capable of supporting tortoise populations continue to decline in area (Berry and Aresco 2014).

The papers in this special section all feature inferences about gopher tortoise populations derived from mark and recapture studies spanning 8–30 years. As the papers will make clear, long‐term studies provide invaluable insights about population dynamics and environmental associations that are unrecoverable or unreliable from shorter‐term studies, especially for this long‐lived species. Unmanipulated tortoise populations are the focus of 2 of the studies, and translocated populations are the focus of 2 others. All the studies occur in the northern, non‐Florida range of the species where population demographics have not been as closely studied and are less understood.

The studies share common analytical features found in contemporary applications. They all make use of Cormack‐Jolly‐Seber or Jolly‐Seber‐based study designs to estimate survival. Where the mark‐recapture sample includes non‐adult size classes, the studies incorporate multi‐state mechanisms to explicitly estimate the probabilistic transitions among size classes (i.e., growth) and size‐class‐specific survival. All the studies use Bayesian methods, which facilitate the handling of missing data, simplify the interpretation of estimated quantities, and enable the direct modeling of informative quantities such as population persistence probability and random effects.

In the paper by Folt et al. (2021), the authors conducted a follow‐on study to that of Goessling et al. (2021), extending the earlier investigation to compare 3 apparently stable and 3 apparently declining sites over 30 years in the Conecuh National Forest, Alabama. Within their models, the authors estimated risk of extinction for each population, and they identified demographic characteristics that distinguished stable from declining populations. This study reveals the importance of site‐specific demographic information for estimating the probability of population persistence.

Tuberville et al. (2021) followed an original study (Tuberville et al. 2008) of a tortoise population translocated to St. Catherine's Island, a coastal barrier island in Georgia. In the current study that spanned 8 years, the authors estimated apparent survival of immature (hatchling, juvenile, and subadult stages) tortoises. They also compared survival rate among 3 types of introduction to the population: hatchling direct release, head‐starting, and wild recruitment. Hatchlings had the same survival rates among all 3 treatments, which provides evidence that translocation has produced a population capable of sustaining itself.

In McKee et al. (2021), the authors estimated apparent survival rates of waif tortoises (tortoises displaced by human collection) translocated to the Aiken Gopher Tortoise Heritage Preserve, South Carolina, at the extreme northern extent of the range. Over the 13‐year study period, the authors found no evidence that annual apparent survival of tortoises translocated as waifs differed from that of unmanipulated populations, indicating that waif tortoises could be used to augment declining, isolated populations.

Hunter and Rostal (2021) analyzed 27 years of mark‐recapture data collected at Fort Stewart, Georgia. Their models permitted estimation of per capita population inflow, emigration, and adult abundance. Yearly data collection allowed the authors to connect demographic rates to prescribed burning regimes, and the authors found differing responses to burning that depended on habitat context. Tortoises primarily responded to burning through movement, indicating that tortoise populations are spatially dynamic when habitat area is large and unrestricted.

The insights gathered from these studies on the long‐term persistence of populations and the effects of management actions like translocation and prescribed burning would not have been possible without long‐term mark‐recapture studies. As these and other studies continue to track marked gopher tortoise populations, additional valuable demographic information will contribute to the conservation and management of this keystone species.

地鼠龟（Gopherus polyphemus）是一种穴居陆龟，特有于美国东南沿海平原的沙质高地，其范围从路易斯安那州东部到南卡罗来纳州西南部再到佛罗里达南部。它发生在多种森林类型中，但也许没有任何生态系统与该物种的生物和文化联系比长叶松树（Pinus palustris）-铁草（Aristida）更紧密。spp。）生态系统。生态系统随着频繁的地面火而演变，维持着相对开放的林冠条件和林地上充足的光线，以满足乌龟的觅食和温度调节需求。地鼠龟曾经很普遍并且很普遍，但是随着欧洲定居，积极抑制火势和成年陆龟的不可持续收割之后，长叶松树林的减少，地鼠龟的数量急剧下降至目前正在评估中的水平，美国濒危物种法。

乌龟是一种极具魅力的物种，其景观中的存在通常被其明显的洞穴和明亮的沙子围裙所掠夺。乌龟的特征使其成为具有历史吸引力的捕获和标记对象。乌龟相对容易捕捉（要有足够的耐心）和处理能力，它们的寿命长，保真度高，因此以后有再次遇到的机会，而且乌龟甲壳的价格便宜且耐用。标记乌龟用于科学研究的第一个已知用途是Goin和Goff（1941），他报道了佛罗里达州中部乌龟的增长1年。

由于意识到了该物种的新出现的保护困境，导致对种群的研究始于1970年代末和1980年代初。在佐治亚州西南部（McRae等 1981）和佛罗里达州中北部（Diemer  1992）的研究表明，标记重获方法可用于了解乌龟运动和种群年龄结构。其他地点的其他研究人员随后进行了更多的商标回收研究。大约在同一时间，在佛罗里达加速了拟定开发地点的陆龟群的大规模易位，导致永久标记动物被释放到接受地点（Ashton和Burke，  2007； Cozad等，  2020）。）。因此，即使能够支撑陆龟种群的栖息地面积持续减少，容纳有陆龟种群的地点的数量（包括几十年前有生命的个体）也在稳步增加（Berry and Aresco  2014）。

在此特殊部分中的所有论文均对从8到30年的标记和捕获研究中得出的有关地鼠龟种群的特征进行了推论。正如论文将明确指出的那样，长期研究提供了有关种群动态和环境关联的宝贵见解，而短期研究尤其是针对这种长寿命物种，是无法恢复或不可靠的。未操纵的陆龟种群是其中两项研究的重点，而易位的种群是另外两项研究的重点。所有研究都发生在该物种的北部，非佛罗里达范围内，该地区的人口统计数据尚未得到深入研究，因此鲜为人知。

这些研究具有当代应用中发现的共同分析特征。他们都利用基于Cormack-Jolly-Seber或基于Jolly-Seber的研究设计来估计生存率。如果标记夺回样本包括非成人大小类别，则研究采用多状态机制来明确估计大小类别（即增长）和特定大小类别生存之间的概率转换。所有研究都使用贝叶斯方法，该方法有助于处理丢失的数据，简化对估计数量的解释，并能够对诸如人口持续性概率和随机效应等信息量进行直接建模。

在Folt等人的论文中。（2021年），作者对Goessling等人的研究进行了后续研究。（2021年），扩大了早期的调查范围，以比较阿拉巴马州Conecuh国家森林在30年中的3个明显稳定的站点和3个明显下降的站点。在他们的模型中，作者估计了每个种群的灭绝风险，并且他们确定了人口稳定与人口减少的人口统计学特征。这项研究揭示了特定地点的人口统计信息对于估计人口持续存在的可能性的重要性。

Tuberville等。（2021），其次原始研究（Tuberville等人。  2008年易位圣凯瑟琳岛，在佐治亚州沿海屏障岛龟人口）。在为期8年的最新研究中，作者估计了未成熟（孵化，少年和亚成年阶段）乌龟的表观存活率。他们还比较了三种引进种群的成活率：孵化直接释放，抢先行动和野生募集。幼雏在所有3种治疗方法中的存活率均相同，这提供了证据表明易位产生了能够自我维持的种群。

在McKee等人中。（2021年），作者估计了在该范围的最北端迁移到南卡罗来纳州艾肯·戈弗勒乌龟遗产保护区的龟（因人类采集而流离失所的乌龟）的表观存活率。在为期13年的研究期内，作者没有发现证据表明，因遗弃而迁移的陆龟的年表观存活率与未受到控制的种群的生存率不同，这表明遗弃陆龟可用于增加数量下降的孤立种群。

Hunter和Rostal（2021年）分析了佐治亚州斯图尔特堡（Fort Stewart）收集的27年标记回收数据。他们的模型可以估算人均人口流入，移民和成年人数量。每年的数据收集使作者能够将人口统计数据与规定的燃烧方式联系起来，并且作者发现对燃烧的不同反应取决于栖息地的情况。乌龟主要通过运动来燃烧，表明当栖息地面积大且不受限制时，乌龟种群在空间上是动态的。

如果不进行长期的标记回收研究，就不可能从这些研究中获得有关人口长期持久性的见解，以及诸如搬迁和处方烧制之类的管理措施的影响。随着这些研究和其他研究继续跟踪标记的地鼠龟种群，更多有价值的人口统计信息将有助于这一主要物种的保护和管理。