Bird Control – Dredging in the Prorva Marine Channel

Nesting birds on islands created by dredging can prevent operations from continuing. The RoBird® company was asked to help a company prevent birds from nesting in order to not inhibit work. With tireless, speedy work and close monitoring, the field team was able to reduce nesting by 75% -83%. Continue reading to learn more.

Prorva marine channel

In 2017 in the eastern Caspian Sea, a company was dredging a channel 68 kilometers long. The dredged material was disposed of on 32 artificial islands, 16 of them submerged and 16 above water. These islands were a suitable habitat for all sorts of animals, from small insects to seals, and varying bird species. The Caspian Sea is also situated on the major migratory routes for many bird species, making it one of the most important regions for the whole Eurasian birdlife ecosystem. Tens of millions of birds pass over the area of the northern, northeastern and eastern coast, twice per year. Hundreds of thousands of birds breed in the area, and many birds choose to stay in the area for the winter.

After a successful operation during the 2016 season, RoBird® was asked for the 2017 season to again implement a bird control operation so the impact on the dredging operation caused by breeding birds would be minimized. Two field teams and an ornithologist then had been active from the start of the dredging in April until the end of August.

The resident specialist and the RoBird® team implemented a bird control operation using a four-step approach of survey, strategy, active operations, and monitoring/adapting to local results and circumstances. The equipment used, were RoBird®, automated and handheld green lasers, and long-range acoustic devices. This was further supported by sticks with streamers and human disturbance. Furthermore, as part of habitat management, six islands were used as buffer islands for birds to populate, and attractive places like spill piles next to smaller access channels were flattened out. The buffer islands were Exclusion Zones for human activity, where the field team and the Marine Mammal Observers (MMOs) were careful not to disturb the bird populations. 

The 2017 season saw a sharp increase in biodiversity and populations compared to the 2016 operations season. 178 bird species were identified during the project compared to 108 in 2016, of which 13 were potential breeders. 11 species had bred at the Prorva site: Caspian gull, Pallas’s Gull, Slender-billed Gull, Common Tern, Caspian Tern, Sandwich Tern, Little Tern, Gull-billed Tern, Kentish Plover, one pair of Common Shelducks, and one pair of Collared Pratincole. The first nine were also the dominant species together with the Black-headed Gull. Multiple of the identified species are on the International Union for Conservation of Nature Red List of Threatened Species.


The operation was a success, albeit highly challenging, with the impact on the dredging operation brought to an absolute minimum. Despite nest and colony forming on some of the active islands, these colonies could be maintained with small exclusion zones. Nesting outside of small exclusion zones could often be prevented, so that dredging could continue as normal. There was one occasion of a temporary decrease in production because of an unexpected nest in danger of being damaged. Also, at one island a speed reduction was enforced in the channel to prevent disturbance of a small colony on spoil piles.

Within the Exclusion Zone consisting of 6 islands, between 2.300 – 3.000 nests were observed or estimated to have occurred. These were minimum estimates, as the Exclusion Zone was only monitored a few times. It is highly likely the actual numbers were much higher. Within the active area consisting of 10 islands, between 840 – 990 nests were observed. This comes down to an effectiveness in nest reduction on a per island basis of between 75% – 83%.

The 2017 season saw highly integrated involvement of bird control, leading to its success despite an enormous increase in populations and breeding pressure. Extensive preparations early during the year led to a well-communicated approach and clear procedures on-site. Fast transport around the Prorva site further meant the field team could be there where they were needed, when they were needed. A well-defined division of responsibilities between the MMO and bird control unit led to clarity and to the opportunity for both roles to support each other if and when needed. Client personnel on the islands assisted at critical times during the season when creating disturbance and minimizing attractive nesting locations, and was of the utmost importance. Therefore the 2017 operation went exceedingly well, and was considered highly successful by both RoBird® and the client. 


If your organization requires wildlife management, the RoBird® team recommends beginning planning early. To arrange for a field team to service your operation, or to lease and train on your own RoBirds®, please send your inquiry to


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