World Maritime Day: Our Black Sea – Our Responsibility and Opportunity

Today we celebrate World Maritime Day – a day dedicated to shipping, the maritime industry, and their vital role in the sustainable development of our oceans.

Maritime transport systems are essential to the global economy, yet they also carry a responsibility to protect the marine environment. Pollution, climate change, and the growing congestion of sea routes call for sustainable solutions and innovation.

Photo: Wix

This year’s theme — “Our Sea – Our Responsibility, Our Opportunity” — is more than symbolic, especially when we look toward the Black Sea and its unique yet endangered inhabitants — the sturgeons.

Sturgeons are not only species of high economic and ecological importance, but also bioindicators of the health of marine and river ecosystems. In the Black Sea region, they are exposed to multiple interacting stress factors that reinforce one another, creating a compounding effect of threats.

Photo: Wix

The maritime transport system is the backbone of the global economy, yet it also impacts marine ecosystems. The introduction of invasive species such as the rapa whelk, which spreads through shipping, demonstrates how human activity alters biodiversity and disrupts food chains.

Additionally, oil spills, wars, and regional conflicts exert further pressure on the marine environment, endangering coastal communities and undermining efforts toward sustainable development.

May 2025 Burgas-Source: Sentinel-1 imagery, 14 May 2025

🌊 What Do the Data Show?

Bulgaria – Southern Black SeaMonitoring along the Southern Black Sea coast reveals alarming trends:

• Fluctuations in oxygen levels

• High concentrations of nitrates and phosphates

• Episodes of turbidity and oxygen deficiency

These conditions place serious pressure on young sturgeons and their potential feeding and migration grounds, reducing their chances for survival and reproduction.

Turkey – The Sea of Marmara

Sampling in Prince’s Islands, the Istanbul coastline, and Izmit Bay (April 2025) shows:

• Electrical conductivity above 23,000 µS/cm

• Nitrate levels between 12–28 mg/L

• Dissolved oxygen from 5.4–8.5 mg/L

• Suspended solids up to 8.6 mg/L

These parameters in an area with intense maritime traffic indicate eutrophication and localized hypoxia risks, threatening the coastal ecosystem and sturgeon habitats.

Ukraine – The Danube and Dnipro Rivers

Over 50 years of systematized Ukrainian data reveal multiple pressures on ecosystems:

• Climate stress: rising water and air temperatures → altered seasonal cycles, reduced ice cover, intensified evaporation

• Hydrological disruptions: the destruction of the Kakhovka Hydropower Plant (2023) → altered water regime and sediment transport

• Eutrophication and salinity: leading to toxic algal blooms and oxygen depletion

• Invasive species: such as Microcystis aeruginosa, disrupting food chains

Adding to these factors, the environmental disaster at the end of 2024—caused by the sinking of two tankers and the subsequent oil spill—further endangered the ecosystem.

Despite this, observations also reveal encouraging signs of recovery, including natural spawning and successful restocking with juvenile sturgeons.

Strategic Conservation Zones:

• Lower Danube (Vilkovo) – one of the last refuges for wild populations in Ukraine

• Dnipro River (Khortytsia Island) – a historical biodiversity hotspot, now with opportunities for restoration after the dam collapse

These zones are critical for sturgeon conservation and underscore the urgent need for international cooperation.

The data from Bulgaria, Turkey, and Ukraine confirm a multiplication of threats and highlight the need for integrated solutions such as:

• Digital mapping and visualization of threats

• Scientific innovation through eDNA analyses and real-time monitoring sensorsThese tools can help restore spawning grounds, reduce pollution, and enable adaptive water resource management.

World Maritime Day is a reminder that our responsibility is directly tied to our actions. The future of the relationship between the maritime industry and marine ecosystems depends on sustainable solutions and innovation:

• Reducing the spread of invasive species

• Optimizing shipping routes and speeds to minimize impacts on marine life

• Investing in “green” technologies and energy-efficient vessels

Shipping can be not only an economic engine but also a partner to nature—if managed with care and innovation.

World Maritime Day is not just a day of celebration—it is a call for stewardship, commitment, and real action.Our Black Sea deserves nothing less.