Marine Pollution and Conservation: Ocean Noise, Overfishing, Invasive Species, and Deep-Sea Mining

What are anthropogenic sounds?

Human-made sounds that contribute to water pollution.

How much faster does sound travel in water compared to air?

About 5 times faster at approximately 1500 m/s.

Why is hearing essential for marine life?

It is crucial for survival, reproduction, communication, and navigation.

What are some sources of ocean noise pollution?

Vessel noise, wind turbines, sonar, seismic surveys, and construction.

What effect does noise pollution have on marine mammals?

It can impair their behavior and cause temporary or permanent hearing loss.

What was the focus of Paper 1's study in New Zealand?

The effects of multiple sound sources on sound frequency.

What did Paper 2 find about 2-stroke and 4-stroke boats' effects on juvenile damselfish?

2-stroke engines caused slower startle responses compared to 4-stroke engines.

What was the main finding of Paper 3 regarding harbor porpoise echolocation?

There was a negative correlation between ocean noise and foraging echolocation.

What did Paper 4 conclude about juvenile giant kelpfish's stress response?

Both intermittent and regular noise induced a stress response affecting growth.

What measures are being taken to mitigate ocean noise pollution?

Designing quieter ships, establishing speed reduction zones, and using bubble curtains.

What is the predicted ambient noise level of the ocean by 2030?

An increase of 5 dB.

What is the current status of marine invertebrate fisheries?

They are among the most harvested marine animals globally, with rapid declines.

What percentage of the marine population is overfished according to Neguez (2021)?

One-third is overfished, and another 60% is fully fished.

What is a major consequence of overfishing marine invertebrates?

It disrupts food chains and can lead to ecosystem collapse.

What are ecosystem overfishing (EOF) indicators?

Tools used to detect cumulative fishing impacts and shifts in trophic levels.

What did the study in the Central Red Sea find regarding overfishing?

It reduced hard coral numbers to zero and increased macroalgae and polychaetes.

What was the focus of the study on Japanese mantis shrimp?

To assess overfishing patterns and management needs in the Shandong Peninsula.

What did the study on U.S. marine ecosystems reveal?

Clear evidence of ecosystem-level overfishing and the need for ecosystem-based management.

What was the impact of unregulated sea cucumber harvesting in Abu Ghosoun?

It caused significant loss of biomass and abundance with no notable recovery.

What is the main problem associated with human activity in the ocean since the industrial revolution?

Increased stress on apex predators due to activities like shipping, fisheries, and pollution.

What role do apex predators play in an ecosystem?

They are crucial for top-down regulation, maintaining the balance of ecosystems.

What are some causes of apex predator decline?

Direct hunting, pollution, accidental catch in fisheries, and climate change.

Why are apex predators particularly susceptible to anthropogenic damage?

They have slow reproduction rates and low population densities due to high energy needs.

What is a trophic cascade?

A process where the loss of apex predators leads to an increase in lower trophic level predators.

What was the impact of the Deepwater Horizon oil spill on toothed whales?

It caused a significant decrease in population density with no recovery detected.

How are juvenile Great White sharks affected by rising ocean temperatures?

Their optimal thermal location is shifting, making them unfit for equatorial regions.

What is the consequence of heavy bycatch in pelagic fisheries for leatherback sea turtles?

It leads to a net population loss of the species.

How is climate change impacting the Guiana dolphin?

It is forcing them to move southward, increasing their risk of population loss.

What threat do baleen whales face despite the cessation of whaling?

Climate change poses a new threat, potentially leading to population crashes.

What mitigation strategies can help protect apex predators?

Stopping whaling, reducing bycatch, and alleviating climate change.

What are Contaminants of Emerging Concern (CECs)?

Pollutants, including pharmaceuticals and personal care products, affecting the environment.

Why are estuaries particularly vulnerable to pharmaceutical pollution?

Due to their unique habitat characteristics and proximity to urban areas.

What are the primary sources of pharmaceutical pollution in estuarine waters?

Wastewater treatment plants and urbanized areas.

What did the study by Reis-Santos et al. (2018) reveal about pharmaceutical compounds?

They detected 32 compounds, mainly antibiotics and beta-blockers, near wastewater treatment plants.

What health risks are associated with PPCPs found in aquatic organisms?

Endocrine disruption, carcinogenic effects, and antibiotic resistance.

What did the study by James et al. (2025) find regarding pharmaceutical pollutants in red drum?

39% of sampled fish contained pharmaceuticals, but at low concentrations.

What mitigation efforts are in place for pharmaceutical pollution in estuaries?

Seasonal testing, removal of pharmaceuticals, and proper disposal measures.

What is the future outlook for pharmaceutical contaminant concentrations in estuaries?

They are expected to rise, leading to increased health risks and altered wildlife behavior.

What is the main problem associated with deep-sea mining?

The potential for severe and long-lasting environmental consequences.

What drives the demand for deep-sea mining?

The increasing demand for rare earth metals and the difficulty of acquiring them.

What is the risk of rushing deep-sea mining without thorough research?

It could lead to major environmental damage and extinction of unknown species.

What are the challenges in researching the effects of deep-sea mining?

Research is difficult, expensive, and time-intensive.

What is the appeal of deep-sea mining for rare earth metals?

It offers an alternative source of metals that are otherwise hard to acquire.

What drives the deep-sea mining industry forward?

The combination of political boundaries and profitable circumstances.

What organization must approve deep-sea mining operations?

The International Seabed Authority (ISA).

What is one major consequence of deep-sea mining?

Harming deep-sea marine environments and causing long-term damage to ecology.

How does disturbing sediments in the deep sea affect carbon storage?

It releases trapped carbon, leading to atmospheric issues.

What did Owen Smith's study focus on?

The long-term effects of mining on megafauna in the Peru basin.

What method did Owen Smith's team use to gather data?

They used ROVs to compile pictures and assess diversity, density, and composition of megafauna.

What did James Asbell's study investigate?

The effects of toxic metals released during deep-sea mining on organisms.

What framework did James Asbell propose for regulators?

The Weight of Evidence framework, which uses multiple forms of scientific evidence for risk assessment.

What did Jason Garcia's study examine?

The intertidal currents in deep ocean ridges and their effects on sedimentation.

What was a key finding from Jason Garcia's research?

Stronger currents led to highly dispersed sedimentation affecting large areas.

What did Samantha Leahy's study reveal about mining impacts?

Mining tracks remained intact after 44 years, showing long-lasting damage to biodiversity.

What are some proposed mitigation strategies for deep-sea mining?

Establishing no-mining zones, conducting more research, and restoration efforts.

What is a potential future outcome of increasing demand for deep-sea minerals?

Expansion of large-scale deep-sea mining, risking irreversible damage to biodiversity.

What is the significance of polymetallic nodules in deep-sea ecosystems?

They provide habitat for deep-sea sessile organisms and take millions of years to form.

What is the impact of introduced species like sea lampreys in the Great Lakes?

They outcompete native species and disrupt local ecosystems due to lack of natural predators.

How did sea lampreys gain access to the Great Lakes?

Through the Welland Canal, bypassing natural barriers like Niagara Falls.

What is a major threat posed by invasive species?

They can cause economic downturns by outcompeting native species and disrupting tourism.

What is the ecological role of sediments in the deep sea?

They act as a major carbon sink, trapping carbon below the surface.

What challenges exist in studying deep-sea ecosystems?

The difficulty of conducting deep-sea studies limits understanding of ecological impacts.

What is the expected recovery time for ecosystems disturbed by deep-sea mining?

Recovery is slow and uneven, with some areas still showing damage decades later.

What is the relationship between deep-sea mining and carbon sequestration?

Mining can disrupt sediment layers that trap carbon, affecting carbon sequestration processes.

What is a potential alternative to ocean mining?

Reducing the demand for rare earth metals and other resources.

What is the role of environmental groups regarding deep-sea mining?

They advocate for moratoriums and more research to understand impacts before mining is allowed.

What are sessile organisms and why are they vulnerable to mining?

They are stationary organisms that cannot escape contaminated sediments during mining.

What is the significance of the 1979 mining test site revisited by Samantha Leahy?

It highlighted the long-term ecological impacts of mining on benthic fauna.

How does deep-sea mining affect nutrient cycling?

It can disrupt the natural processes that support nutrient cycling in marine ecosystems.

What species negatively impacted salmon, trout, and sturgeon populations?

The sea lamprey

How many eggs can a single female sea lamprey produce in one spawning season?

Around 100,000 eggs

What program was initiated in the 1950s to control sea lamprey populations in the Great Lakes?

The sea lamprey control program (SLCP)

What chemical is commonly used to reduce sea lamprey populations?

TFM (a lampricide)

What is the typical reduction percentage of lamprey populations achieved by lampricides?

Around 80% or higher

What are some non-chemical methods used to control sea lamprey populations?

Electric weirs, adjustable dams, and electrofishing devices

What is a significant drawback of using lampricides?

They also reduce populations of native lampreys and sturgeons

What invasive species competes with native seagrass and affects nutrient cycling?

Caulerpa racemosa

What impact do European green crabs have on seagrass ecosystems?

They damage and graze on seagrass

What is the purpose of the study on Sargassum muticum and Zostera marina?

To determine the effect of Sargassum muticum on Zostera marina and examine limpets as biological vectors

What is the relationship between lionfish and seagrass habitats?

Lionfish consume fish that help control macroalgae, which competes with seagrass

What is the effect of intensive megaherbivore grazing on native seagrass?

It reduces the volume of native seagrass, compromising sediment stabilization

What is the correlation between seagrass canopy volume and erosion protection?

Higher seagrass canopy volume is positively correlated with better erosion protection

What is a major threat posed by the green crab to marine ecosystems?

It preys on native organisms and outcompetes them

What mitigation strategy is suggested for invasive species in Dominica?

Using personal fish traps made of mesh to prevent invasive grasses from establishing

What is the best way to mitigate the introduction of invasive species?

Avoiding the introduction of species into new habitats

What ecological role do native seagrasses play in coastal environments?

They provide shelter for fish and stabilize sediments

What is 'invasional meltdown'?

A phenomenon where introduced species facilitate each other, leading to compounded negative effects

What is the focus of future prevention and conservation efforts regarding seagrass?

Preventing seagrass degradation and preserving native biodiversity

How do dense seagrass meadows affect the establishment of invasive species?

They offer resistance to establishment and spread of invasive species

What challenges does climate change pose to seagrass ecosystems?

It increases vulnerability and drives grazing species into seagrass habitats

What is the significance of monitoring chemical effects of lampricides?

To understand their impact on native species and ecosystem health

What is the impact of invasive seagrass on juvenile fish species in the U.S. Virgin Islands?

It displaces native seagrass that serves as a nursery for juvenile fish

What are the potential consequences of uprooting native seagrass by storms?

Increased erosion of sediment and difficulty for natives to reestablish

What is a key factor in the resilience of native seagrass habitats?

Maintaining healthy habitats and preventing ecological degradation