While large-scale oil spills can cause acute mortality events in birds, there is increasing evidence that sublethal oil exposure can trigger physiological changes that have implications for individual performance and survival. Therefore, improved methods for identifying small amounts of oil on birds are needed. Because ultraviolet (UV) light can be used to identify thin crude oil films in water and on substrate that are not visually apparent under normal lighting conditions, we hypothesized that UV light could be useful for detecting small amounts of oil present on the plumage of birds. We evaluated black skimmers (Rynchops niger), brown pelicans (Pelecanus occidentalis), clapper rails (Rallus crepitans), great egrets (Ardea alba), and seaside sparrows (Ammodramus maritimus) exposed to areas affected by the Deepwater Horizon oil spill in the Gulf of Mexico as well as from reference areas from 20 June, 2010 to 23 February, 2011. When visually assessed without UV light, 19.6% of birds evaluated from areas affected by the spill were determined to be oiled (previously published data), whereas when examined under UV light, 56.3% of the same birds were determined to have oil exposure. Of 705 individuals examined in areas potentially impacted by the spill, we found that fluorescence under UV light assessment identified 259 oiled birds that appeared to be oil-free on visual exam, supporting its utility as a simple tool for improving detection of modestly oiled birds in the field. Further, UV assessment revealed an increase in qualitative severity of oiling (approximate % of body surface oiled) in 40% of birds compared to what was determined on visual exam. Additionally, black skimmers, brown pelicans, and great egrets exposed to oil as determined using UV light experienced oxidative injury to erythrocytes, had decreased numbers of circulating erythrocytes, and showed evidence of a regenerative hematological response in the form of increased reticulocytes. This evidence of adverse effects was similar to changes identified in birds with oil exposure as determined by visual examination without UV light, and is consistent with hemolytic anemia likely caused by oil exposure. Thus, UV assessment proved useful for enhancing detection of birds exposed to oil, but did not increase detection of birds experiencing clinical signs of anemia compared to standard visual oiling assessment. We conclude that UV light evaluation can help identify oil exposure in many birds that would otherwise be identified visually as unexposed during oil spill events.

尽管大规模的溢油事故可能导致鸟类死亡，但越来越多的证据表明，亚致死油暴露可以触发生理变化，这些变化对个体的表现和生存都有影响。因此，需要用于识别鸟类上少量油的改进方法。由于紫外线（UV）可用于识别在正常照明条件下在视觉和视觉上看不见的水和基质上的原油薄膜，因此我们假设紫外线可用于检测鸟类羽毛中的少量油脂。 。我们评估了黑ski（Rynchops niger），褐鹈鹕（Pelecanus occidentalis），拍手栏（Rallus crepitans），大白鹭（Ardea alba））和海边的麻雀（Ammodramus maritimus）从2010年6月20日至2011年2月23日暴露于墨西哥湾深水地平线漏油事件影响的区域以及参考区域。在没有紫外线的情况下进行目视评估时，有19.6％的鸟类来自受墨西哥湾影响区域溢出的油被确定为上油（先前公布的数据），而在紫外线下检查时，确定有56.3％的相同禽类有油暴露。在可能受到泄漏影响的地区检查的705个人中，我们发现，在紫外光评估下的荧光鉴定出259只油禽，这些肉禽在目视检查中似乎是无油的，这支持了它作为改进检测中等油禽的简单工具的效用。场。进一步，紫外线评估显示，与目视检查相比，在40％的禽类中上油的定性严重程度有所提高（大约为身体表面上油的百分比）。另外，使用紫外线确定的暴露于油中的黑色脱脂奶，棕色鹈鹕和大白鹭遭受了红细胞的氧化损伤，循环红细胞的数量减少，并以网状红细胞增加的形式显示了再生血液学反应的证据。这种不良反应的证据类似于在不使用紫外线的情况下通过目视检查确定的在暴露于油中的禽类中发现的变化，并且与可能由于暴露于油中的溶血性贫血相一致。因此，紫外线评估被证明有助于加强对暴露于油中的鸟类的检测，但与标准的视觉注油评估相比，并没有增加对出现贫血临床体征的鸟类的检测。我们得出结论，紫外线评估可以帮助识别许多禽类中的油脂暴露，否则在漏油事件中肉眼可以识别为未暴露。