Ok, here’s a million dollar question: is the Caribbean really dying? Or, more specifically, are marine species found on Caribbean reefs becoming less abundant?

好吧，这是一个百万美元的问题：加勒比海真的死了吗？ 或者，更具体地说，加勒比海珊瑚礁上发现的海洋物种是否减少了？

To answer this question we’ll need to pick our weapons of analysis, namely…

要回答这个问题，我们需要选择分析武器，即…

1. An annual time series plot.年度时间序列图。
2. Linear regression with weights.带权重的线性回归。

Surprisingly, these tried and true methods give us plenty of insight into the data (we’ll find an excuse to break out neural nets another day). In the meantime, we have four plots below, each of which shows a different marine organism’s average annual count over the past 22 years. So, let’s jump right in.

出乎意料的是，这些经过实践检验的真实方法为我们提供了对数据的大量洞察力(我们会找到借口再突破神经网络)。 同时，我们在下面有四个图，每个图显示了过去22年中不同海洋生物的平均年计数。 因此，让我们直接进入。

硬珊瑚和软珊瑚的分析 (Analysis of Hard and Soft Corals)

The first of our charts depicts the centerpiece, the make-or-break of any coral reef: hard corals. Hard corals, or reef-building corals, are fantastically intricate living rocks. They provide both food and shelter to a wide range of marine organisms. Long story short, without reef-building corals, reefs would not exist.

我们的第一张图表描绘了核心，即任何珊瑚礁的成败：硬珊瑚。 坚硬的珊瑚，或造礁的珊瑚，是错综复杂的活石。 它们为多种海洋生物提供食物和庇护所。 长话短说，没有造礁珊瑚，就不会有珊瑚礁。

Now the amount of hard coral is often measured by percent coverage, that is, from a birds-eye-view, the percent of an area that is covered. In Figure 1 (left), we can see that the weighted regression line has a slope of -0.3; this corresponds to a 0.3 decrease in percent coral coverage every year.

现在，硬珊瑚的数量通常是通过覆盖率百分比来衡量的，也就是说，从鸟瞰角度来看，所覆盖区域的百分比。 在图1(左)中，我们可以看到加权回归线的斜率是-0.3。 这相当于每年珊瑚覆盖率下降0.3。

0.3%? That’s it? Yes we’ve lost roughly 7.2% of our coral coverage in the past 22 years. But remember this is percent coverage; using the fitted values, the total percent change is -28%. Moreover, prior research suggests that since the 1950’s, we’ve lost around 50% of Caribbean hard corals.

0.3％？ 而已？ 是的，在过去22年中，我们已经失去了大约7.2％的珊瑚覆盖率。 但是请记住，这是百分比覆盖率； 使用拟合值，总变化百分比为-28％。 此外，先前的研究表明，自1950年代以来，我们损失了大约50％的加勒比硬珊瑚。

Dying: 1.

垂死：1。

Not-Dying: 0.

未死：0。

For our second case, let’s look at soft corals. Soft corals are the Robin to a hard coral’s Batman. Rooted at the base similar to a tree, they grow upwards in search of sunlight and can often be seen flowing in ocean currents. While they have less structural importance than their harder counterparts, soft corals are still an integral part of reef food chains.

对于第二种情况，让我们看一下软珊瑚。 软珊瑚是硬珊瑚蝙蝠侠的罗宾。 它们像树一样扎在树根上，向上生长以寻找阳光，经常看到它们在洋流中流动。 尽管它们的结构重要性不如较坚硬的珊瑚，但软珊瑚仍然是珊瑚礁食物链中不可或缺的一部分。

As shown in Figure 2, soft corals show an even stronger negative trend relative to their initial value. They too have decreased by about 7.2%, but because they started with only 11.6% total cover, their percent change is -57.4%. In 2019, the average diver would see a striking 1.7% cover for soft corals.

如图2所示，软珊瑚相对于其初始值显示出更大的负趋势。 它们也下降了约7.2％，但由于它们最初仅覆盖11.6％的总覆盖率，因此其变化百分比为-57.4％。 在2019年，普通潜水员的软珊瑚覆盖率将达到惊人的1.7％。

Despite this dismal trend, it’s interesting to note that after almost every decrease in percent cover, soft corals appear to rebound. Once again we have evidence that nature can be resilient when given the opportunity.

尽管出现这种令人沮丧的趋势，但有趣的是，在几乎每度减少百分比覆盖率之后，软珊瑚似乎就会反弹。 我们再次有证据表明，如果有机会，大自然可以复原。

Reasons for coral mortality are well-documented and have been for the past 15 years. Despite a long list of culprits, the most cataclysmic cause of coral death is the infamous coral bleaching, which occurs when water temperatures become too hot or cold. There were around five main bleaching events in the Caribbean that overlap with our time series, but I would like to highlight three that occurred in 1997, 2005, and 2015. Let me know if you see any relationships.

珊瑚死亡的原因已有充分的文献记载，并且已经过去15年了。 尽管有大量罪魁祸首，但造成珊瑚死亡的最主要灾难性原因是臭名昭著的珊瑚褪色，这是在水温过高或过低时发生的。 加勒比地区大约有五起主要的漂白事件与我们的时间序列重叠，但我想强调一下三起发生在1997年，2005年和2015年的事件。如果您有任何关系，请告诉我。

鱼的分析 (Analysis on Fish)

The above information is not new. However, relatively little time series analysis has been done on things that move, for example, fish.

以上信息不是新的。 但是，对诸如鱼的移动物体进行的时间序列分析相对较少。

So, on to the third of four figures. Here we will be looking at the prolific yet uniquely colorful butterfly fish. Fun fact of the day: butterfly fish mate for life. A less fun fact (but still reasonably fun) is butterfly fish are omnivorous but rely on coral for a large portion of their diets.

因此，到四个数字的第三个。 在这里，我们将研究多产但独特的彩色蝴蝶鱼。 一天的有趣事实：蝴蝶鱼终生相伴。 一个不那么有趣的事实(但仍然很有趣)是蝴蝶鱼是杂食性的，但是大部分时间都依赖珊瑚。

As shown in Figure 3 to the left, butterfly fish counts have declined precipitously over the past 22 years. Moreover, there is a striking resemblance to the trends exhibited by hard coral, lagged by roughly a year. For instance, the plunge in coral from 2006–2011 is almost identical to the plunge in butterfly fish from 2007–2012.

如左图3所示，在过去22年中，蝴蝶鱼的数量急剧下降。 而且，与硬珊瑚表现出的趋势有着惊人的相似，大约滞后了一年。 例如，2006-2011年珊瑚的暴跌几乎与2007-2012年蝴蝶鱼的暴跌相同。

Using a weighted regression line to summarize, over the past 22 years the average number of butterfly fish per dive has decreased by a count of 10, equating to a 52.5% decline.

使用加权回归线进行总结，在过去22年中，每次潜水的蝴蝶鱼平均数量减少了10个，相当于下降了52.5％。

Dying: 3.

垂死：3。

Not-Dying: still 0.

未死：仍为0。

It’s not looking good

不好看

On to the final figure. In this graph we will be discussing the aptly named parrot fish. Arguably the ugliest beautiful fish, the parrot fish is brightly colored from beak to tail. Yes, it has a beak.

到最后的数字。 在此图中，我们将讨论恰当命名的鹦鹉鱼。 可以说，鹦鹉鱼是丑陋的最丑的美丽鱼，从喙到尾巴颜色鲜艳。 是的，它有喙。

Parrot fish use this beak to break off chunks of hard coral and because they adhere to a strict coral diet, one would expect their numbers to be closely linked to hard coral percent cover.

鹦鹉鱼使用这种喙来分解坚硬的珊瑚，并且由于它们坚持严格的珊瑚饮食，因此人们希望它们的数量与坚硬的珊瑚覆盖率紧密相关。

According to Figure 4, that theory has some supporting evidence. In 2005, the year of arguably the most catastrophic bleaching event in recent Caribbean history, we see a massive drop-off in fish counts. However, the symmetry between butterfly fish and hard coral is surprisingly not observed with parrot fish.

根据图4，该理论有一些支持证据。 在2005年，可以说是近代加勒比海历史上最灾难性的漂白事件，我们看到鱼类数量大幅度下降。 然而，鹦鹉鱼却没有发现蝴蝶鱼和坚硬的珊瑚之间的对称性。

Now, why the spike in 2018? Great question. After looking through the literature, there was no conclusive evidence.

现在，为什么会在2018年飙升？ 好问题。 查阅文献后，没有确凿的证据。

However, despite our lack of understanding of the drivers of these trends, we can still observe and summarize them: parrot fish have decreased by 48% over the past 22 years with a year over year change of -0.57 in counts per dive.

但是，尽管我们对这些趋势的驱动力缺乏了解，但我们仍然可以观察和总结它们：鹦鹉鱼在过去22年中下降了48％，每次潜水计数同比变化了-0.57。

A side note, parrot fish showed one of the strongest negative trends out of all fish observed.

附带说明，鹦鹉鱼是所有观察到的鱼中最强烈的负面趋势之一。

结论 (Conclusion)

Hopefully this analysis was able to shed some light onto our initial question of “is the Caribbean really dying?” While these four species (or grouping of species in the case of hard and soft corals) are by no means a representative sample of the Caribbean, they certainly can be used as proxies for reef health. And, it’s clear that hard corals, soft corals, butterfly fish, and parrot fish are all in decline.

希望这一分析能够阐明我们最初的问题“加勒比海真的死了吗？” 虽然这四个物种(或硬或软珊瑚而言，不是物种的集合)绝不是加勒比地区的代表性样本，但它们无疑可以用作珊瑚礁健康的代理。 而且，很明显，硬珊瑚，软珊瑚，蝴蝶鱼和鹦鹉鱼都在下降。

Personally, what makes these problems so interesting (other than sharks are cool) is the fact that a large portion of society has ignored these findings. Is it charity burnout? Maybe. But I think observing these trends is almost pointless; we already know this stuff. Instead, we need to build tools that quantify and forecast ocean damage, ideally in dollars.

就个人而言，使这些问题如此有趣(除了鲨鱼很酷)的原因是，很大一部分社会都忽略了这些发现。 是慈善倦怠吗？ 也许。 但是我认为观察这些趋势几乎是没有意义的。 我们已经知道这些东西。 相反，我们需要构建工具来量化和预测海洋破坏，最好以美元为单位。

That’s my humble opinion. If you have thoughts or ideas, please leave a comment or reach out.

那是我的拙见。 如果您有想法或想法，请发表评论或联系。

资料来源 (Sources)

• Animals, A. (2019, November 08). Butterfly Fish. Retrieved August 14, 2020, from https://a-z-animals.com/animals/butterfly-fish/

  Animals，A.(2019年11月8日)。 蝴蝶鱼。 于2020年8月14日从https://az-animals.com/animals/butterfly-fish/检索

• Buddemeier, R. W. (2003). Coral Reef Decline in the Caribbean. Science, 302(5644), 391c-393. doi:10.1126/science.302.5644.391c

  布德迈尔，RW(2003)。 加勒比海的珊瑚礁下降。 科学， 302 (5644)，391c-393。 doi：10.1126 / science.302.5644.391c

• Caribbean coral reef decline began in 1950s and 1960s from local human activities. (2020, April 22). Retrieved August 14, 2020, from https://www.sciencedaily.com/releases/2020/04/200422214047.htm

  加勒比珊瑚礁的下降始于1950年代和1960年代，原因是当地的人类活动。 (2020年，4月22日)。 于2020年8月14日从https://www.sciencedaily.com/releases/2020/04/200422214047.htm检索

• Crcp. (2016, April 19). NOAA’s Coral Reef Conservation Program (CRCP) — Coral Facts. Retrieved August 15, 2020, from https://coralreef.noaa.gov/education/coralfacts.html

  Crcp。 (2016年4月19日)。 NOAA的珊瑚礁保护计划(CRCP)-珊瑚事实。 于2020年8月15日从https://coralreef.noaa.gov/education/coralfacts.html检索

• Muñiz-Castillo, A. I., Rivera-Sosa, A., Chollett, I., Eakin, C. M., Andrade-Gómez, L., Mcfield, M., & Arias-González, J. E. (2019). Three decades of heat stress exposure in Caribbean coral reefs: A new regional delineation to enhance conservation. Scientific Reports, 9(1). doi:10.1038/s41598–019–47307–0

  Muñiz-Castillo，AI，Rivera-Sosa，A.，Chollett，I.，Eakin，CM，Andrade-Gómez，L.，Mcfield，M.，＆Arias-González，JE(2019)。 加勒比珊瑚礁暴露于热应力的三十年：加强保护的新区域划定。 科学报告， 9 (1)。 doi：10.1038 / s41598–019–47307-0

The data were collected by Reef Check, a coral conservation non-profit that trains volunteer divers to collect marine data. With 1576 unique entries for the Caribbean ranging from 1997–05–24 to 2019–08–24, there were plenty of data points to conduct a TS analysis. However, due to variations in the dive sites, specifically location and time, annual means for the entire Caribbean were calculated. Finally, the least squares regression line was weighted to account for the number of samples each year; early and modern years had less dives than middle years.

数据是由珊瑚礁非营利组织Reef Check收集的，该组织培训志愿潜水员收集海洋数据。 从1997–05–24到2019–08–24，在加勒比地区共有1576个唯一条目，其中有大量数据点可以进行TS分析。 但是，由于潜水地点，地点和时间的差异，计算了整个加勒比海地区的年均收入。 最后，对最小二乘回归线进行加权，以说明每年的样本数量。 早期和现代的潜水次数少于中年。

Here is the code.

这是代码 。

Note: these are my findings. If you would like to contact me, leave a message here. All criticisms are welcome.

注意：这些是我的发现。 如果您想与我联系，请在此处留言。 欢迎所有批评。