Seed dispersal in Andalusian olive groves by frugivorous birds

All methodological information and farms and landscape characteristic information can be found in Rey et al (2021). Characterization of the avian seed dispersers and the seeds they mobilizes by mist-netting: From September 2019 to March 2020, we conducted bird mist-netting sessions in the 20 study olive farms monthly. Birds trapping was carried out for 3 h in each session (between mid-morning and noon). For each farm, two simultaneous capture zones, one in the olive field and the other in SNWH patches were considered, with a distance of 150 meters between zones. In each zone (habitat), we set two mist-nets of 12 ?? 2.5 meters and a mesh size of 16mm (24 linear meters of the net in total per zone). In each mist-net zone, a sound call that emitted songs of the frugivorous species present was arranged at random to attract birds. A 1-m wide strip of mosquito net was placed on the ground beneath the mist nets to collect the seeds excreted by the birds while they were trapped in the net. Once a bird was released from the net it was immediately introduced in a cloth bag with a paper cone located inside until the moment of seed collection/identification. All birds were kept in the cloth bags for 1 h, then ringed and released. For each individual captured, the total number of seeds of each species collected under the net and in the collector was recorded. Mobilised seeds to seed fall traps: - Seed_trap_2018: To determine the probability of seed deposition into different habitats within the olive farm and to characterize seed rain, we used plastic plant pots of 40 cm diameter and 20 cm depth as seed fall traps. Traps were covered with a 1 ?? 1 cm wire mesh to avoid seed predation by micro mammals and perforated on their base to drain rainwater. 18 seed fall traps were placed per farm in three different types of habitats (6 traps per habitat): beneath the olive tree canopy, beneath the canopy of isolated overtopping non-olive trees serving as perches to birds within the olive field, and within seminatural woodland habitat remnants. Traps were always set hanging from branches of trees and/or tall scrubs. Traps were active for 17 months, between October 2018 and March 2020 in 9 localities. We collected the trapped seeds periodically (every 3 months, with monthly-bimonthly checks to make sure that the traps were active). - Seed_trap_2021: in this case, we used plastic plants trays of 57 x 42 cm and 10 cm depth as seed fall traps. Traps were covered with a 1 ?? 1 cm wire mesh to avoid seed predation by micro mammals and perforated on their base to drain rainwater. 30 seed fall traps were placed per farm in seminatural woodland habitat remnants below fleshy- fruited shrub, other shrubs and perches. The traps were active for 6 months, between June 2021 and March 2022 in 12 localities. We collected the trapped seeds monthly.

所有方法学信息、农场及景观特征信息均可参见Rey等人（2021）的研究。
利用雾网对鸟类种子传播者及其所传播种子的特征表征：
2019年9月至2020年3月期间，我们每月对20个研究样地橄榄园开展鸟类雾网采样工作。每次采样时长为3小时（时段为上午中段至正午）。每个橄榄园设置2个同步采样区，分别位于橄榄田与SNWH斑块内，两区间距为150米。每个采样区（生境）内布设2张12×2.5米的雾网，网孔尺寸为16毫米（每个采样区总网长为24线性米）。每个雾网采样区随机布设播放现存食果鸟类鸣唱的声音回放装置，以吸引鸟类。在雾网下方地面铺设1米宽的蚊帐条带，用于收集被困网中鸟类排泄的种子。鸟类从网中被取出后，会立即被放入内部装有纸漏斗的布袋中，直至完成种子收集与鉴定工作。所有鸟类在布袋中放置1小时后，会被佩戴脚环并放生。针对每只捕获的鸟类，记录其网下及收集装置中收集到的各物种种子总数。
种子雨陷阱收集的传播种子：
Seed_trap_2018：为明确种子在橄榄园不同生境中的沉降概率并表征种子雨特征，我们采用直径40厘米、深度20厘米的塑料花盆作为种子雨陷阱。陷阱上方覆盖1×1厘米的金属网，以防小型哺乳动物捕食种子，底部打孔以排出雨水。每个橄榄园在3类不同生境中布设18个种子雨陷阱（每类生境6个）：橄榄树冠层下方、橄榄园内作为鸟类停栖点的孤立高大非橄榄树树冠层下方，以及半自然林地生境残块内。陷阱均悬挂于树木或高灌丛的枝条上。该批次陷阱于2018年10月至2020年3月在9个样点布设，运行时长17个月。我们定期（每3个月一次，期间辅以每月至每双月的检查以确保陷阱正常运作）收集陷阱内的种子。
Seed_trap_2021：本批次采用尺寸为57×42厘米、深度10厘米的塑料托盘作为种子雨陷阱。陷阱上方覆盖1×1厘米的金属网，以防小型哺乳动物捕食种子，底部打孔以排出雨水。每个橄榄园在半自然林地生境残块内的肉质果灌丛、其他灌丛及停栖点下方布设30个种子雨陷阱。该批次陷阱于2021年6月至2022年3月在12个样点布设，运行时长6个月，我们每月收集一次陷阱内的种子。