Department of Geology, William and Mary, PO Box 8795, Williamsburg, VA 23187, USA.
Virginia Institute of Marine Science, William and Mary, Route 1208 Greate Road, Gloucester Point, VA 23062-1346, USA.
Philos Trans R Soc Lond B Biol Sci. 2019 Dec 23;374(1788):20190209. doi: 10.1098/rstb.2019.0209. Epub 2019 Nov 4.
The eastern oyster plays a vital role in estuarine habitats, acting as an ecosystem engineer and improving water quality. Populations of Chesapeake Bay oysters have declined precipitously in recent decades. The fossil record, which preserves 500 000 years of once-thriving reefs, provides a unique opportunity to study pristine reefs to establish a possible baseline for mitigation. For this study, over 900 fossil oysters were examined from three Pleistocene localities in the Chesapeake region. Data on oyster shell lengths, lifespans and population density were assessed. Comparisons to modern , sampled from monitoring surveys of similar environments, reveal that fossil oysters were significantly larger, longer-lived and more abundant than modern oysters from polyhaline salinity zones. This pattern results from the preferential harvesting of larger, reproductively more active females from the modern population. These fossil data, combined with modern estimates of age-based fecundity and mortality, make it possible to estimate ecosystem services in these long-dead reefs, including filtering capacity, which was an order of magnitude greater in the past than today. Conservation palaeobiology can provide us with a picture of not just what the Chesapeake Bay looked like, but how it functioned, before humans. This article is part of a discussion meeting issue 'The past is a foreign country: how much can the fossil record actually inform conservation?'
牡蛎在河口栖息地中起着至关重要的作用，它是一种生态系统工程师，可以改善水质。切萨皮克湾牡蛎的数量在最近几十年急剧下降。化石记录保存了 50 万年曾经繁荣的珊瑚礁，为研究原始珊瑚礁提供了一个独特的机会，以建立一个可能的缓解基线。在这项研究中，从切萨皮克地区的三个更新世地点检查了超过 900 个化石牡蛎。评估了牡蛎壳长度、寿命和种群密度的数据。与现代样本进行比较，这些样本来自类似环境的监测调查，结果表明，化石牡蛎比来自多盐度区的现代牡蛎更大、寿命更长、数量更多。这种模式是由于现代种群中优先捕捞更大、生殖能力更强的雌性个体所致。这些化石数据与现代基于年龄的生殖力和死亡率估计相结合，使得估算这些早已死亡的珊瑚礁的生态系统服务成为可能，包括过滤能力，过去的过滤能力比现在高出一个数量级。保护古生物学可以为我们提供不仅是切萨皮克湾的样子，还有人类之前它是如何运作的画面。本文是讨论会议议题“过去是一个陌生的国度：化石记录到底能在多大程度上为保护提供信息？”的一部分。
