Praia da Vitória Marsh

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Praia da Vitória Marsh was designated as a Wetland of International Importance (Ramsar Site) under the Ramsar Convention on 13-12-2012.

More about the site

The Praia da Vitória Marsh is a swamp-type coastal wetland of brackish water influenced by tides, located in the urban centre of this city. This aspect, together with its physical and ecological characteristics, makes it unique in the bio-geographical region of Macaronesia, where only one more ecosystem of this type is known, located in the Canary archipelago, therefore on a very different geographical location, less centralized in the Atlantic and near the African continent. In the Azores there are other coastal wetlands, including in the municipality of Praia da Vitória, in particular the Belo Jardim Marsh and the Pedreira Marsh in Cabo da Praia parish. However, the Praia da Vitória Marsh is the first wetland rehabilitated in the Azores in an urban area, very close (within minutes) from the airport and the commercial city port, features that make it easily accessible not only for the local population, but also for visitors, thereby enhancing it as a place of excellence for environmental education and specialized tourism – birdwatching.

On a hydrological level, and due to the topography of the location, it functions as a collecting basin of superficial fluidity of the surrounding hydrographic basin, under the influence of the oscillations in the base aquifer by fluctuations in the sea water level. This gives this ecosystem an important role as a mediator of the natural water flux, contributing to flood control and the aquifer maintenance.

Aside from the marsh’s main visible water area, there are some sites that are permanently soaked during the times of year with greater rainfall. The marsh is a formation that is essentially made up of freshwater, with sea water penetration, making its water brackish. Because the marsh is close to the coastline, this penetration occurred by periodic overtopping of the dune belt. Today, it is restricted to the passage through the channel that was initially built for drainage. The freshwater that supplies the marsh is essentially of underground provenance. Due to the marsh’s quota close to the sea level, its plain intercepts part of the base aquifer, by emersion of the water table. The superficial flow of the watershed also contributes to the freshwater supply.

Studies were made regarding the measurement of water quality, including salinity and conductivity, and concluded that the Marsh had a brackish gradient resulting from the confrontation of the three elements (surface runoff, infiltration, and aquifer oscillation of sea water). This gradient keeps stable in time and space, fostering a greater diversity of ecological niches and biodiversity associated with these, which differentiates it from other coastal wetlands in the islands that constitute the Macaronesian region.

The Praia da Vitória Marsh biotope can be individualized and it has its own fauna, flora and biocommunities that support a considerable diversity of organisms and intense biological processes.

The Praia da Vitória Marsh is associated with a significant number of flora species, some characteristic and dominant in this type of ecosystems, such as the Juncus sp. and the Cyperus eragrostis, as well as others introduced into it casually like the Ricinus communis.

In 1991, according to HP (1991), the natural heritage of the Praia da Vitória Marsh sheltered close to 190 species, distributed in 23 biotopes and habitats. Some of those species were rarely seen in the Azores, including resident and migratory species. Presently, this number keeps relatively up to date.

One of the characteristics associated with wetlands in general, and with this one in particular, lies in the brevity of the food chain, of which main primary consumer is the avifauna.

The Praia da Vitória marsh is, by its location in the North Atlantic Ocean, approximately midway between the American and European continents, a strategic point for birds that, for various reasons, come into marginal routes during their migrations. Thus, over time, there has been registered presence of birds from America and Europe that find refuge for food and rest when encountering an adversity that deviates from their normal migration route.

The simultaneous presence of birds from America and Europe, driven by the location of this ecosystem at the confluence of several streams, makes it a unique and strategic location for birdwatching in the Macaronesian context. This uniqueness is underlined by the interest of the international community of birdwatchers.

The Praia da Vitória Marsh has a flora biodiversity distributed in a considerable number of distinct areas, among others: ruderal area (e.g., Cichorium intybus, Torilis arvensis and Lavatera cretica); wetlands of freshwater dominance (e.g., Cyperus eragrostis and Lythrum junceum); wetlands of halophyte dominance (e.g., Scirpus maritimus and Juncus acutus), and pasture areas (e.g., Trifolium pratense).

The list of the registered flora in the Praia da Vitória Marsh includes 87 flora species, of which three are endemic to the Azores and one endemic to Macaronesia. The IUCN Red List of Threatened Species establishes five species as LC (Least Concern) and one as NT (Near Threatened).

The specific vegetation in the area of the Praia da Vitória Marsh and its hydrological conditions provide for the appearance of several types of fauna, namely, mammals, fish, birds and arthropods. However, it is especially the migratory avifauna that most benefits from these types of ecosystems by finding a strategic area of refuge and food when faced with adverse conditions in their normal migration route.

Located in the Azores archipelago, thus belonging to the Palearctic, the Praia da Vitória Marsh is also home to species, not only from the zoogeographical region to which it belongs, but also, and very often, from the Nearctic. Because it is located in the middle of the North Atlantic Ocean, between the Americas and Europe, the Praia da Vitória Marsh is an excellent site for the observation of American species (e.g., Ardea herodias, Anas americana and Fulica americana) and European species (e.g., Ardea cinerea, Fulica atra and Anas crecca). The simultaneous observation of these species makes it special birdwatching on this site.

During the whole year it is possible to observe several species (e.g., Egretta garzetta, Aythya sp. and Larus sp.), some of which are endemic subspecies from the Azores such as: Columba palumbus azorica, Buteo buteo rothschildi, and Motacilla cinerea patriciae. In addition, Paul da Praia da Vitória is one of the few places in the Azores archipelago where Gallinula chloropus and Fulica atra nesting occurs regularly.

The list of registered fauna presently in the Praia da Vitória Marsh includes 94 fauna species that are divided into eight taxonomic groups. Of the species listed, 13 are endemic to the Azores and one to Macaronesia. The Species are covered by various conservation statutes, including the Habitats Directive (92/43/CEE) that identify one species in Annex IV, the Birds Directive (79/409/CEE) that identifies six species in Annex I, five in the Annex II and 11 in Annex II/III. The Bern Convention identifies seven species in Annex II and eight in Annex III. The Washington Convention (CITES) recognizes two species in Annex A and four species in Annex C. The Bonn Convention identifies 20 species in Annex II. Finally, the IUCN Red List of Threatened Species establishes 60 species as LC (Least Concern), two as NT (Near Threatened), one as CR (Critically Endangered – Anguilla anguilla), and one EN (Endangered – Nyctalus azoreum).

The Praia da Vitória Marsh is presently used as a recreation site, and for the city it is an important green site for leisure, namely with the presence of a playground and a skate and radical sports park, as well as a place for annual festivities. It is also used for educational and environmental awareness purposes, mainly with younger students, thanks to its proximity (less than a kilometer away) to a campus composed of several primary schools, a secondary and a vocational school. It is considered to be an excellent strategic point for bird watching, and an added value for tourism and local development. In terms of scientific investigation, it is an excellent site for the study of this type of ecosystem’s biodiversity and behavior.

The Praia da Vitória Marsh is presently used as a recreational site, and for the city it is an important green site for leisure, namely with the presence of a playground and a skate and radical sports park, as well as a place for annual festivities. It is also used for educational and environmental awareness purposes, mainly with younger students, thanks to its proximity (less than a kilometer away) to a campus composed of several primary schools, a secondary and a vocational school. It is considered to be an excellent strategic point for birdwatching and an added value for tourism and local development. In terms of scientific investigation, it is an excellent site for the study of this type of ecosystem’s biodiversity and behavior.

The environmental space of Paul da Praia da Vitória has established itself, over the last few years, as the city’s green leisure space. It is equipped with a shelter for birdwatching, some information boards about the biodiversity present, sanitary facilities, waste collection, living areas, children’s area, pedestrian paths, and a games area.

Information about its restoration process and environmental values is available at the Environmental Interpretation Center of the Praia da Vitória Wet Green Infrastructure and in the book “The Wetlands at Praia da Vitória, Terceira: reconstruction of an Açorean memory”.  Visits can be accompanied by a guide whenever requested to the management entity.

The site is located in the urban centre of the city of Praia da Vitória, the second city of the island, to which is associated a landscape, bathing areas and history of excellence. Besides, the Praia da Vitória Marsh, as with the other marshes in the county, is considered by the international birdwatchers community to be a hotspot for avifauna observation, being especially interesting as the junction of American and European species, species whose records of sightings are in the various specialty websites. It is that frequent and numerous record that reinforces the importance of Paul as a hotspot for nationally and internationally. The record sightings of species of birds can be found at various sites (;;

Inside the Praia da Vitória Marsh there is an area for entertainment shows throughout the year, especially during the Municipality’s Festivities in the summer.

The Marsh is located in the urban frame of the city and less than a kilometer away from an elementary, middle and high schools, and a vocational school. With its high environmental-valued ecosystem, the Marsh has been an excellent site for environmental education. It has held many environmental awareness sessions organized by the Municipality and solicited by schools.

The Praia da Vitória Marsh has aroused the interest of many investigators and been basis for many studies published in academic papers, such as Graduation, Miguel, 2004, Goulart, 2011, Master’s Degree Barata, 2002 and Rocha, 2002 and more recently for a PhD that is still in course. This is due in part to the Marsh’s localization inside the urban frame of the city. But its ecosystem (especially the high diversity of water salinity as a result of the confluence between the base aquifer, the lines of water from the hydrographic basin, and sea water) represents a strong potential in terms of ecological niches and biodiversity.

Presently, the Praia da Vitória Marsh is one of the places in the municipality where more environmental awareness sessions and activities are held, addressing environmental issues related to the various descriptors (water, waste, biodiversity), and arousing awareness of the importance of an ecosystem in a regulatory perspective water, and its importance for resident and migratory birds.

The requalification of the site surrounding the Praia da Vitória Marsh has been intended since the island’s colonization. The Marsh has been seen for a long time as a troublesome site that needed human intervention, since the first settlers and until the past century, since the European culture looked at wetlands as sites that had to be intervened in and reused for other purposes.

Therefore, in the 18th century the first project was presented. It aimed to transform the Marsh’s area into a safe haven. This project of military engineering was never implemented and the Marsh’s site began degrading with the increase of demographic pressure in its surroundings.

The need to protect the town that was growing around the bay from the ocean’s effects led to the building of a protective wall which began in 1926. It was this construction that definitely broke the marsh’s dune dynamic and its direct connection to the sea. Without this direct connection (which allowed for at least an annual renewal of the marsh’s water), the marsh’s ecosystem was largely affected and began posing a public health threat due to the poor quality of the water and plagues that found ideal conditions for their development.

During WWII, the construction of a military port inside Praia da Vitória’s bay and a connection road between the port and the Lajes airfield (installed by the North American forces stationed in Terceira) limited, although partially, the marsh’s north site.

With the help of the economic and mechanical power of the North American forces stationed in Lajes, the City Hall at the time proposed an embankment of the marsh’s site, stating reasons of insalubrities and public health deriving from the marsh’s degradation.

The works for the embankment of the marsh’s site were held in the following three decades, and reached a conclusion in the 90’s when the site was transformed into a huge green area complementary to a soccer field that was created in the early stages of the embankment process. The green area was made up of a large field with a couple of shade trees, ornamental plants and even the attempt to create an endemic plants garden.

In the meantime, there were many projects that intended to give a different use to the site, from a zoo to a golf course. In the 1990’s there was a more structured project from the HP Company that integrated an interesting ecological study about the site.

Recognizing the marsh’s importance and its environmental value only happened after 2002. It was at that time that the municipality began seriously thinking about recovering the marsh as a wetland.

At an early stage a work team was brought together, composed of specialists in several areas: Hydrogeology, Soils, Climatology, Water Quality, Botany and Nature Conservation. This work team developed specific studies requested by the Municipality of Praia da Vitória, which definitely assumed the wetland recovery project.

At the same time that the studies were being developed, several interventions were made in the site. First, the excavation of a contiguous area, although not communicating, with the small area of water that survived the embankment of the old marsh, in order to study the ecosystem’s reaction to the projected intervention.

The new area of water reacted apparently well and at the end of a week it was perfectly stabilized (which was demonstrated by the chemical analysis of the water that demonstrated similar characteristics to the old area of water). The Praia da Vitória Municipality ordered the opening of a second area of the old marsh of greater dimensions than the first one and the result was similar in terms of water characteristics.

In 2005, the Praia da Vitória Marsh recovery was integrated in the contract for the “renewal and extension of the Praia da Vitória marginal and environmental/touristic park of the Marsh”. The project included the recovery of part of the wetland as the basis for a site that one expects to respect its natural vocation and at the same time to serve the needs of the human community that is in contact with nature.

Therefore, three distinct zones were defined within the Marsh’s site. A zone restricted to human presence and that emphasizes the existence of the marsh ecosystem in a more complete way; an intermediate zone where human presence is allowed in less disturbing activities for the ecosystem; and a zone where people can walk freely and enjoy the radical sports and skate parks, playground, and an area for the city’s festivities with marsh ecosystem surroundings. The amount of water present in the no-human zone is larger than in the playgrounds. Nevertheless, the existence of water helps the existence of a salinity gradient in the body of water (which nourishes biodiversity), frames the different valences, and keeps the ecosystem present.

Once the excavation and terrain modelling works were over, in 2009, there began the systematic monitoring of the ecosystem. This was done through weekly water analysis of PH parameters, ORP, salinity and conductivity done with a mobile device. There was also the systematic monitoring for the presence of fauna, especially avifauna and weekly records of sightings as well as the monitoring of existing flora during spring.

The proliferation of algae, especially during seasons of higher temperatures, has led to an annual physical removal of algae. These algae have been the target of two identification studies, carried out in 2010 and 2011, concluding that species were Gayralia oxysperma, Cladophora coelothrix, Blidingia marginata, Cladophora álbida, Cladophora hutchinsiae and Ulva intestinalis.

In an attempt to let more sea water directly into the Marsh, a connection was built on the other side of the Marsh, which led to better local control of the proliferation of algae. There is the perception that in order to make the ecosystem sustainable in the future, a direct connection to the sea is required.

The stabilizing of a large mirror of water has created a considerable ichthyofauna community which was also studied by a specialized team of investigators from the University of the Azores.

There have been records of the sightings of avifauna species considered to be very rare in several specialized sites (;;

These species were of European and American origin, which shows us that the Marsh serves not only locals but also a specific niche for tourism: national and international birdwatching. With this in mind, several infrastructures were built to support and stimulate this activity, such as observatories and information boards with basic information about the existent flora and avifauna.

Since 2009, there exists and is being implemented a plan for monitoring water quality and the presence of birds in Paul da Praia da Vitória, which calls for the measurement, three times a week, using a portable meter of the parameters pH, ORP, Temperature, Conductivity and Salinity.

In addition, the regular monitoring is confirmed by often biennial laboratory analyses. Laboratory analyses also include the measurement of CBO (Biochemical Oxygen Demand), CQO (Chemical Oxygen Demand), Kedjal Nitrogen and Total Phosphorus.

Sightings of birds are compared and supplemented with the entries made in the specialty websites for the same data.

For two years now, there has been implemented a plan for the physical removal of algae as a way to control the excessive proliferation of those organisms. The operation constitutes the removal of algae which are pulled out of water. After it dries, it is forwarded to the composting of green materials implemented by the Municipality.

On the banks of the lake have been an enhanced installation of native vegetation through the seed (the case of reeds) and the minimal intrusion of space just to eliminate weeds. The management of vegetation in the remaining space is made by cutting it regularly, monthly or bimonthly depending on the growth rate except for the spring time of year, which widens the gap between cuts to allow flowering and thus facilitate the identification of existing flora.

On the entry of domestic animals (dogs and cats), this information is highlighted as well as all other aspects in the code of conduct that is posted at the main entrances into the park.

There is an eutrophication combat plan that includes the physical removal of macroalgae from the marsh water, with an increase of the entrance of sea water so as to approximate the present hydrodynamic with past observed hydrodynamic values.

The physical removal of the mass of algae has been implemented in 2010 and 2011. In 2011 a pipeline link was built between the end of Paul and the sea, which would get water in Paul with the rising tide. In general, none of these actions to date proved effective in combating the proliferation of algae (constancy over time and space).

There is the perception that Paul can never be a sustainable natural ecosystem, until it is reconstituted with its direct connection to the sea. However, the infrastructure which delimits this wetland, and which stands between it and the sea, is still too important to the functioning of the city and its marina.

The Paul da Praia da Vitória is one of the three wetlands for which the Praia da Vitótia Coastal Wet Green Infrastructure Management Plan was prepared, approved and put into practice since 2018.   


Latest update of those information: march 2022