Contaminant Burden in Seabirds: Biomonitoring for Environmental Conservation

by

Introduction

People now regard seabirds as crucial species barometers, particularly for the health of ocean ecosystems. The marine ecosystem places these birds at the top of the food pyramid, making them more susceptible to the bioaccumulation of various environmental pollutants. Researchers study pollutants in seabird species, including traditional chemicals like PCBs and new threats like PFAS. Seabird exposure allows for numerous studies of marine ecosystems. Supervising the concentration of contaminants in seaborne birds is now considered a major work in conservation practices because it can tell about the intensity of pollution in certain environments. Biomonitoring is a non-lethal way to find out how exposed seabirds are to toxic substances. Typically, researchers collect samples from seabirds, including feathers, blood, eggs, and preen oil. Following is a breakdown of the contents of this blog on how contaminant burden assessments in seabirds contribute to environmental conservation: origins of various contaminants, effects on seabird population, and persistent biomonitoring.

Contaminants in Seabirds: An Overview

Proximic contamination Seabirds absorb complex mixtures of pollutants through their diets and interactions with water resources. Polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) are some common hazardous compounds that seabirds often encounter. Furthermore, the seabird population has recently discovered contaminants, such as polycyclic aromatic hydrocarbons (PAHs) and per- and polyfluoroalkyl substances (PFASs). Such pollutants are not readily biodegradable and can accumulate in seabirds’ tissues, which has serious consequences for their health.

Many parts of the world no longer manufacture PCBs and OCPs due to their hazardous nature for both wildlife and humans. However, because of their cyclical and enduring behavior, they remain in the environment for several decades after release and continue to impact marine species. For instance, a study assessing the contamination levels in flamingo chicks in the Ebro Delta of Spain revealed multi-contamination at a very early age, suggesting that young birds continue to be exposed to contamination in their breeding grounds. Therefore, while the earlier contaminants were present in seabirds at various places, new pollutants such as PFASs are now being noted. Consumer products containing industrial chemicals or surfactants, known as PFASs, bioaccumulate in the liver and blood of seabirds.

Yearwise Publication Trend on “environmental conservation”

Find publication trends on relevant topics

Biomonitoring as a Conservation Tool

Seabird biomonitoring entails taking samples from the bird, such as feathers, blood, eggs, or preen oil, without euthanizing them, and then determining the concentration of contaminants within the bird. This type of analysis has proven beneficial in identifying potential impacts of pollutants on marine birds and contributes to determining areas of high pollution. Choosing sample type plays a crucial role in evaluating different types of pollutants. For instance, feathers are the most common test for mercury, whereas blood is more appropriate for POPs and heavy metal pollutants.

The type of biological material also depends on the research objectives and seabird population conservation principles. Sa However, new indicator pollutants, including PFASs and pharmaceutical pollutants, require analysis of blood and preen oil samples. Several studies have demonstrated that feathers and egg samples are effective matrices with which to measure PCBs, OCPs, and PBDEs. However, new indicator pollutants, including PFASs and pharmaceutical pollutants, require analysis of blood and preen oil samples.

Subsequently, results revealed differences in exposure levels of various pollutants due to seabird habitat use, diet, and life history. Researchers have found higher contamination concentrations in birds collected from coastal areas or areas close to industrial, I-authority, and smokestack vegetation than in birds collected from other areas. The study titled “Anti-pestane exposure in seabirds: a comparison of shearwaters from NE Atlantic and Mediterranean islands” discovered that the levels of contaminants vary depending on where the colonies are located, with higher levels found in the Mediterranean. These variations emphasize the need to engage in geographical biomonitoring to know the environment where one lives.

Contaminants of Concern

PCBs and OCPs: Hence Seabirds’ bodies accumulate high concentrations of PCBs and OCPs due to their past industrial and agricultural use. We particularly recognize these substances for their high environmental persistence and ability to accumulate in animal tissues. Researchers have previously investigated PCB and OCP contamination in seabird eggs using temporal trends. These contaminants reduce reproductive success, cause developmental deficits, and cause immunosuppressive disease in seabirds, all of which necessitate permanent analysis for conservation plans.

PFASs: Known for their water and stain repellent properties, PFASs are a group of chemicals widely used in various products. PFASs are especially worrisome because they are rather chemically stable and essentially persistent within the environment; they are also highly bioaccumulative. The authors analyzed blood samples taken from flamingo chicks and discovered elevated levels of PFOA and PFOS in the chicks’ tissues. Researchers have linked the compounds in these foods to hazardous health consequences among wildlife, including liver toxicity, development toxicity, and carcinogenicity.

My research also revealed that seabirds encounter PAHs, a class of organic compounds that arise from the incomplete combustion of fossil fuels and other organic materials. Seabird tissues contain some of the identified PAHs, particularly in areas affected by oil spills. Supervision of PAH exposure is important. These compounds have demonstrated toxicity and carcinogenicity. Biomonitoring’s technological advancements have improved the measurement of PAHs in seabird blood samples and liver tissue, indicating an increased level of environmental contamination.

Recent Publications on “environmental conservation”

Find publications on relevant topics

The Impact on Seabirds and Marine Ecosystems

The presence of contaminants in seabirds is not only an indication of the birds’ health status but also of the marine environment’s health. Seabirds are important link species in marine food chains, and toxic contamination can affect other organisms in the chain. For instance, toxicity in seabirds strongly affects reproductive success, lowers survival probabilities, and causes declines in population frequencies. This, in turn, can disrupt the predator-prey balance and the general mix of species in terms of their capacity to live afloat in the oceans.

Exposure to contaminants leads to behavioral changes in areas such as foraging, movement, and use of space. Further biomonitoring initiatives are required to detect new emerging contaminants in the future and assess their long-term effects on seabird populations. A study involving Cory’s shearwaters in the Mediterranean Sea showed that during breeding, seabirds behave and move within different habitats in line with the levels of contamination. Seabirds, therefore, are considered a vital bioindicator organism in terms of changes in ecosystem status due to pollution.

Future Directions in Seabird Biomonitoring

Further biomonitoring initiatives are required to detect new emerging contaminants in the future and assess their long-term effects on seabird populations. Non-lethal sampling techniques are necessary to monitor the emissions of new pollutants such as PFAS and pharmaceutical products, and researchers have to employ and improve such techniques in the future. Also, biomonitoring needs to be done in different places and at different times to see how well the global pollution control measures are working and to find out how much pollution there is from pollutants that stay at high levels for long periods of time.

An important weakness in seabird biomonitoring is the lack of numerous systematic studies that would provide data on the interactions of many contaminants. While seabirds often encounter multiple concentrations of pollutants, most previous investigations have focused on a single class of contaminants. It means that the identification of their combinations and their effects on the health of seabirds is potentially very useful as a base for potential future conservation management programs.

However, the use of biomonitoring data depends on the continued cooperation of researchers, non-governmental environmental organizations, and policymakers. By incorporating seabird biomonitoring into larger marine conservation projects, we can work towards improved marine resource conservation and sustain the health of these ecological systems.

Conclusion

Seabirds, a significant group of birds, play a crucial role in bioassaying the health of marine systems, and their contamination profiles offer valuable insights into pollution trends. Sample seabirds for pollution to determine the presence of historic and novel pollutants and the impact of ecology on their health. It is necessary to implement intervention measures for pollution hazards that affect marine life. Addressing the questions and problems remains crucial if we aim to deepen our understanding of how chemicals impact seabirds and continue our efforts to safeguard these bioindicators and their habitats.

References

  1. Moradi, V., Halldorson, T., Idowu, I., Xia, Z., Vitharana, N., Marvin, C., Thomas, P.J. and Tomy, G.T., 2023. Microbead-Beating Extraction of Polycyclic Aromatic Compounds from Seabird Plasma and Whole Blood. Separations, 10(1), p.48.
  2. Dulsat-Masvidal, M., Bertolero, A., Mateo, R. and Lacorte, S., 2023. Legacy and emerging contaminants in flamingos’ chicks’ blood from the Ebro Delta Natural Park. Chemosphere, 312, p.137205.
  3. Pacyna-Kuchta, A.D., 2023. What should we know when choosing feather, blood, egg or preen oil as biological samples for contaminants detection? A non-lethal approach to bird sampling for PCBs, OCPs, PBDEs and PFASs. Critical Reviews in Environmental Science and Technology, 53(5), pp.625-649.
  4. Bianchini, K., Mallory, M.L., Braune, B.M., Muir, D.C. and Provencher, J.F., 2022. Why do we monitor? Using seabird eggs to track trends in Arctic environmental contamination. Environmental Reviews, 30(2), pp.245-267.
  5. Morin-Crini, N., Scheifler, R., Amiot, C., Riols, R. and Coeurdassier, M., 2022. Determination of polycyclic aromatic hydrocarbon (PAH) contents in micro-volumes of the whole blood and liver of Red Kite by a simplified GC-MS/MS method. International Journal of Environmental Analytical Chemistry, 102(4), pp.834-843.

Top Experts on “environmental conservation“