Black Mambas Rack Up Heavy Metals in Their Scales, Helping to Track Urban Pollution – Discover Magazine

Report on Black Mamba (*Dendroaspis polylepis*) as a Bioindicator for Urban Pollution and its Contribution to Sustainable Development Goals

1.0 Introduction

A recent study published in Environmental Pollution has identified the black mamba (*Dendroaspis polylepis*) as a significant bioindicator for heavy metal pollution in urban environments. Research conducted in Durban, South Africa, demonstrates that these reptiles accumulate environmental pollutants in their bodies, providing critical data for assessing urban environmental health. This report outlines the study’s findings and analyzes their direct implications for achieving several United Nations Sustainable Development Goals (SDGs), particularly those concerning urban sustainability, public health, and biodiversity.

2.0 Research Methodology and Findings

The study focused on analyzing heavy metal concentrations in black mambas from various land-use zones within the Durban metropolitan area.

2.1 Data Collection

• Samples were collected from snakes located in industrial, commercial, and domestic properties, as well as from nature reserves.
• Non-invasive methods, such as clipping scales from live snakes, were utilized, aligning with ethical wildlife handling and supporting SDG 15 (Life on Land) by promoting the conservation of species.
• Tissue samples from deceased snakes were also analyzed to provide a comprehensive dataset.

2.2 Key Findings

1. Heavy Metal Accumulation: Significant levels of heavy metals, including lead, arsenic, cadmium, and mercury, were detected in the snakes’ scales and tissues.
2. Correlation with Land Use: Snakes from industrial and commercial areas exhibited substantially higher concentrations of heavy metals compared to those from green spaces and nature reserves. This direct correlation establishes them as reliable indicators of localized pollution.
3. Biomagnification: Black mambas accumulate these pollutants through their diet, primarily rodents and birds, which ingest contaminants from the local environment. This positions the snake as a key indicator at a higher trophic level.

3.0 Implications for Sustainable Development Goals (SDGs)

The application of this research provides a valuable tool for monitoring and advancing key SDGs.

3.1 SDG 11: Sustainable Cities and Communities

• The study offers a cost-effective and practical method for monitoring pollution levels in urban areas, contributing to Target 11.6 (reduce the adverse per capita environmental impact of cities).
• Findings that show lower pollution in green spaces reinforce the importance of urban planning that incorporates and protects natural habitats, contributing to Target 11.7 (provide universal access to safe, inclusive and accessible, green and public spaces).

3.2 SDG 3: Good Health and Well-being

• By identifying hotspots of heavy metal pollution, this research helps authorities mitigate public health risks associated with exposure to environmental toxins, supporting Target 3.9 (substantially reduce the number of deaths and illnesses from hazardous chemicals and air, water and soil pollution).
• The ecological role of black mambas in controlling rodent populations also contributes to public health by limiting the spread of rodent-borne diseases.

3.3 SDG 15: Life on Land

• This research reframes the perception of a feared species, highlighting its crucial ecological value and promoting its conservation. This supports Target 15.5 (take urgent and significant action to reduce the degradation of natural habitats, halt the loss of biodiversity).
• Using snakes as environmental monitors demonstrates the intrinsic value of biodiversity and encourages the protection of terrestrial ecosystems.

4.0 Conclusion

The study confirms that the black mamba is a highly effective bioindicator for assessing heavy metal pollution in urban ecosystems. This research not only provides a new methodology for environmental monitoring but also underscores the interconnectedness of urban development, public health, and biodiversity conservation. By leveraging the ecological function of species like the black mamba, stakeholders can advance multiple Sustainable Development Goals, fostering healthier, more sustainable urban environments and promoting a greater appreciation for the role of wildlife in maintaining ecosystem balance.

Analysis of Sustainable Development Goals in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

   The article on black mambas as pollution trackers connects to several Sustainable Development Goals (SDGs) by highlighting issues of environmental health, urban sustainability, and biodiversity conservation.

   • SDG 3: Good Health and Well-being: The article touches upon health by discussing the accumulation of hazardous heavy metals in the environment, which poses a risk to both wildlife and human health. It also mentions the health impact of snakebites.
   • SDG 11: Sustainable Cities and Communities: The research is set in the urban environment of Durban, South Africa, and directly addresses urban pollution from industrial and commercial activities. It also suggests that the findings can inform urban planning, specifically regarding the need for green spaces.
   • SDG 12: Responsible Consumption and Production: The source of the pollution is identified as industrial and commercial properties, linking the issue to patterns of production that release heavy metals into the environment.
   • SDG 15: Life on Land: This is a central theme, as the article focuses on a specific species (black mamba) and its role as a bioindicator for ecosystem health. It discusses the impact of pollution on wildlife, the importance of the snake in its ecosystem (controlling rodent populations), and the need to change human perceptions to reduce human-wildlife conflict and conserve the species.

2. What specific targets under those SDGs can be identified based on the article’s content?

   Based on the issues discussed, the following specific SDG targets are relevant:

   • Target 3.9: “By 2030, substantially reduce the number of deaths and illnesses from hazardous chemicals and air, water and soil pollution and contamination.” The study’s focus on identifying heavy metals like “lead, arsenic, cadmium, and mercury” in the environment directly relates to this target of reducing illness from hazardous chemical pollution.
   • Target 11.6: “By 2030, reduce the adverse per capita environmental impact of cities…” The article’s use of snakes to measure pollution levels in Durban is a method of assessing the city’s environmental impact. The finding that “snakes from industrial and commercial areas had far higher metal levels” points directly to this urban environmental impact.
   • Target 11.7: “By 2030, provide universal access to safe, inclusive and accessible, green and public spaces…” The article explicitly states that the research can inform “the need for more green spaces in cities,” which is a key component of this target.
   • Target 12.4: “By 2020, achieve the environmentally sound management of chemicals and all wastes throughout their life cycle… and significantly reduce their release to… soil…” The accumulation of heavy metals from industrial sources in the ecosystem is a direct consequence of failing to meet this target. The study highlights the need for better management of these chemical pollutants.
   • Target 15.5: “Take urgent and significant action to reduce the degradation of natural habitats, halt the loss of biodiversity and… protect and prevent the extinction of threatened species.” The article advocates for a change in public perception to protect black mambas from being killed due to fear and human conflict. It emphasizes their value, stating, “snakes in general can play a valuable role as biomarkers for environmental health, and should preferably be left to live in peace.”

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

   The article implies several specific indicators that can be used to measure progress:

   • Indicator for Targets 3.9, 11.6, and 12.4: The primary indicator presented is the concentration of heavy metals (lead, arsenic, cadmium, mercury) in the tissues of bioindicator species like the black mamba. The article states, “If the body tissue of individuals contain high levels of heavy metals, it is a strong sign that the local environment is under threat.” A reduction in these concentration levels over time would indicate progress in reducing pollution.
   • Indicator for Target 15.5: An implied indicator for biodiversity protection and reducing human-wildlife conflict is the reduction in mortality rates of black mambas from human conflict. The article mentions snakes dying from “human conflict,” and the researchers’ hope to mend public perception implies a goal of reducing these killings. The stability of the black mamba population in its natural and urban-adjacent habitats could serve as another measure of progress.

4. Create a table with three columns titled ‘SDGs, Targets and Indicators” to present the findings from analyzing the article. In this table, list the Sustainable Development Goals (SDGs), their corresponding targets, and the specific indicators identified in the article.

   SDGs	Targets	Indicators
   SDG 3: Good Health and Well-being	3.9: Reduce deaths and illnesses from hazardous chemicals and pollution.	Concentration levels of heavy metals (lead, arsenic, cadmium, mercury) in bioindicator species.
   SDG 11: Sustainable Cities and Communities	11.6: Reduce the adverse per capita environmental impact of cities.	Levels of heavy metal accumulation in wildlife within different urban zones (industrial, commercial, green spaces).
   	11.7: Provide universal access to safe and accessible green spaces.	Difference in pollution levels between snakes from green spaces versus industrial areas, highlighting the environmental quality of green spaces.
   SDG 12: Responsible Consumption and Production	12.4: Environmentally sound management of chemicals and wastes.	Presence and concentration of industrial heavy metals in the local ecosystem, as measured in snake tissues.
   SDG 15: Life on Land	15.5: Halt biodiversity loss and protect threatened species.	Reduction in the number of snakes killed due to human conflict; stability of local snake populations.

Source: discovermagazine.com