Waterbird conservation promotes important energy flow between rice paddies and nearby Important Bird Areas in Cuba
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Rice is the main food of the daily Cuban diet. In order to satisfy the national demand, some of Cuba’s wetlands have been converted for agriculture, including into rice paddies. This has resulted in a high loss of natural wetland habitat for biodiversity. Cuba is the biggest island in the Caribbean lying in the middle of important waterbird migration corridors, including the Atlantic and Mississippi Flyways, and is also host to some of the last significant populations of a number of Caribbean wetland dependent bird species, such as the Vulnerable West Indian Whistling-duck (Dendrocygna arborea). Rice paddies have been considered as a possible emerging alternative habitat for waterbirds. After the 90’s (a period of extended economic crisis in Cuba that followed the dissolution of the Soviet Union) food shortages and the lack of fossil fuels transformed agriculture from industrialized and specialized to sustainable and organic agriculture. Many areas of state land were lent to families in small and medium subsistence units to grow rice and other crops for their own and community consumption, and the remainder was given to the state to guarantee the presence of crops and commodities in the national market. The use of natural fertilizer and few chemicals, fields in varying stages of flooding and drainage, and low impact harvesting methods lead to high levels of vertebrate and invertebrate biodiversity turning the rice paddies into important bird feeding areas while nearby wetlands provide resting and nesting areas for migrant and resident waterbirds. Nevertheless, only waterfowl (mainly ducks) were perceived as crop pests by the farmers who persecuted and killed them. Since the 1980’s, the Bird Ecology Team of the University of La Havana has been doing research on the ecology of the waterbird populations in the rice paddies and nearby wetlands. These studies supported the international recognition of two rice paddies with neighboring coastal areas as Important Bird Areas (IBAs): Humedal Sur de Pinar del Rio and Humedal Sur de Sancti Spiritus. They have found that waterbirds benefit the crops through weed and pest control and natural fertilization promoting an energy flow through both systems - natural and ‘alternative’ wetlands provided by rice paddy. The team has been working closely with farmers to convince them not to kill the birds but to regard them as beneficial to their rice crops and to manage them in favour of biodiversity and rice.
rice paddies, Cuba, wetlands, waterbirds, Important Bird Areas
Dr. Lourdes Mugica Valdés is Auxiliar Professor at the University of Havana's Faculty of Biology in Cuba. She has taught there since 1982, involved in both formal ecology courses and in the faculty's research and environmental education programs. She is part of Havana University's Bird Ecology Group. Dr. Martin Acosta Cruz is Full Researcher at the University of Havana and the head of the University's Bird Ecology Group, which is widely recognized for its contribution to our knowledge of Cuban waterbird ecology. He has been involved in the research of birds and rice culture in Cuba since 1978. They are both considered world leaders in the study of rice paddies as an important habitat for aquatic bird species and have made a great contribution to the knowledge and research of Cuban waterbird ecology. Ms. Verónica Anadón Irizarry is the Caribbean Program Manager for BirdLife International. She has been supporting the development, management and implementation of BirdLife’s Caribbean Program since 2005.
1.Regional Profile and the importance of rice cultivation in the national and local economy
Cuba is the largest and most westerly island of the insular Caribbean, accounting for over 50% of the region’s land area. Mainland Cuba is 1,250 km long and averages 150 km wide. Vast plains occupy 79% of the land area but are interrupted by four mountain systems, and the mainland is surrounded by four archipelagos comprising over 4,000 cays. Climate, geography and topography have combined to produce a wide diversity of ecosystems and, as a result, Cuba is the most biologically diverse island in the West Indies. More than 50% of the flora and 30% of the vertebrate fauna are endemic to the island. Cuba is home to 366 species of bird of which 28 are endemic to the island, and 32 are considered globally threatened. Its long shape and low geomorphology holds the most extended wetlands, especially coastal, of the Caribbean region. Wetlands in Cuba provide important foraging, resting and breeding grounds for many waterbirds, from migratory species to residents.
Rice farming is an important part of the Cuban economy (it is the second most important crop after sugar cane). Agriculture contributes less than 10 percent to the gross domestic product (GDP), but it employs roughly one fifth of the working population. About 30 percent of the country’s land is used for crop cultivation.
Rice in Cuba is grown throughout all provinces but the main paddies can be found in the south coast on the borders of natural coastal wetlands in Pinar del Río, Matanzas, Sancti Spíritus, Camagüey and Granma. In some cases, the wetlands are a fringe of coastal lagoons and mangroves of about 1 km wide (Pinar del Río, Sancti Spíritus, Camagüey); others constitute extensive areas, with swamps, mangroves, numerous channels and lagoons (Ciénaga de Birama, in Granma and Ciénaga de Zapata, in Matanzas). The close proximity of natural areas and the rice paddies favors the constant movement of waterbirds between them and the consequent interchange of material and energy in both areas.
Figure 1: Large scale rice harvesting in Los Palacios rice paddies, Cuba
Rice has been grown in Cuba since 1750, with a significant increase in the scale of production in 1967. Cubans consume 56 kg per capita which makes it very important in their diets. However, this consumption is highest among the rural and farming population who are the producers of this cereal, and who in the 1960s produced it mainly to satisfy family needs. During the 1980s Cubans developed the specialized production of rice and by that time were able to provide 60% of the national demand, cultivating nearly 130 000 ha. Afterwards in the 1990s, during the economic crisis that followed the dissolution of the Soviet Union, market production dropped significantly. This period transformed Cuban society and the economy due to the severe shortage of fossil fuels. As a result energy dependent systems such as transportation, industry and agriculture were unable to operate. Hunger was experienced with national food shortages. In a response to the lack of food, sustainable and organic agriculture was introduced in low and medium-sized sustainable units. Moreover, the state and communities started to organize the creation of co-operatives to work the land and support each other in production. Much of the state land was lent to farmers to grow rice, with more than 22,814 ha distributed from which 17,446 ha are currently cultivated by farmers and individuals who distribute the crop for self-consumption and to their community. Following the creation of these small and medium-sized subsistence units, the cost of rice dropped by 60 % making it affordable within the national market. However, recently the price has increased due to fluctuations in the international market price. This way of cultivating rice continues, producing crops at small and medium scale for national Cuban consumption. Furthermore, efforts are being made to increase national rice production to decrease dependence on imports from abroad, since the international market price for rice is considered high for the country.
The historical demand for rice in Cuba has led to the conversion of natural wetlands into agricultural fields. Working as alternative wetlands, rice fields are productive feeding grounds for many birds, and also important nesting and resting habitat for other species. They have an elevated carrying capacity that permits the development of high bird populations and invertebrates that exceed those of natural areas. In Cuba, about 10% of the endemic plants and 50% of Cubans birds are associated with them.
2. The Use and Management of Natural Resources in the Region
2.1 The Use and Management of Natural Resources in the Past and Present
Rice cultivation has been practiced in Cuba from around 200 years, shortly after colonization by the Spanish. At that time farming was done by hand and with the use of animals. Agricultural machinery pulled by animals was first used by the end of that period and the crop system employed was of dry land and in others surface-irrigated land. A rice development program started in 1967 with the objective of achieving self-sufficiency in rice production. In Latin America, Cubans come second in terms of their consumption of rice, with an average per capita consumption of 56 kg per year, which creates a national demand for 450,000 tons.
Cuba’s tropical climate favors rice cultivation almost year round. Seeds can be sown all year with the exception of the period from the end of August through to the middle of November (for about 3 months) because seeds sown at that time form panicles at the coldest time of year (December and February) causing flower sterility and empty grains. Rice paddies occupy extensive areas with varieties yielding on average 4.9 tons/ha and an annual production nationally of more than half a million tons. However, the yield per hectare remains lower than the average in Central American and Caribbean countries. Cultivation goes through a wet and dry cycle, and since rice is grown constantly over large areas, there are always fields in varying stages of flooding and draining, leading to high levels of vertebrate and invertebrate biodiversity. This characteristic makes possible the management of high bird diversity, which moves from one field to another as birds move to maintain their specific requirements. Harvesting is done twice a year, limited in part to shortage of water, lack of fertilizers and modern agricultural technology. This activity generates more than 20,000 jobs on public (state owned) farms.
2.2 The Problems Associated with the Use and Management of Natural Resources and its Impact on Biodiversity
There are growing, conflicting concerns regarding the bird community associated with rice cultivation. Rice farmers were concerned about crop losses presumed to be caused by birds, whereas conservationists are concerned about the value of the paddies as bird habitat and thus about the implications of the agricultural management techniques for the bird community. Consumption of rice seeds is the major negative impact that birds may have on the rice yield. However, rice is an important source of food for many waterfowl species and they could benefit from the rice not collected during the harvest.
In the last 15 years chemical use has been reduced by c. 50%, which has turned the rice paddies into important bird feeding areas, while neighboring wetlands are resting and nesting areas. The reduction in the use of pesticides and herbicides in Cuba presumably is a main factor in the dramatic increase in the population of various waterbirds (e.g. Glossy Ibis Plegadis falcinellus and Black-necked Stilt Himantopus mexicanus).
Figure 2: Waterfowl in Sur del Jibaro rice paddies just before spring migration
2.3. Regional Plans and Other Measures toward Resolution of the Above Problems
An integrated approach is being proposed as a solution to these problems: the rice Agro-ecosystem. Birds are clearly an important biotic component of the rice agro-ecosystem. A better understanding of the role birds play in the energy flow and nutrient cycle will be essential if an ecological approach to improving agriculture and wildlife is to take a hold. Research aims to determine the role of rice paddies in bird conservation, and the threat posed by the indiscriminate use of chemicals that pollute the natural environment.
3. Understanding the relationship between rice cultivation and birds
3.1 Research and outreach
The Grupo de Ecología de la Universidad de la Havana has carried out research since 1978 to gain knowledge about the ecology of waterbirds in natural and alternative wetlands. The group’s findings have helped change the attitudes of farmers towards birds on their rice paddies – an important development, given that the two most important wetlands in the country, the Zapata Swamp and the Birama Swamp, both have rice plantations in nearby areas which are heavily used by birds.
Figure 3: Researchers from the Grupo de Ecología de la Universidad de la Havana
Combining research with an active environmental education program, wetland training workshops and the development of local groups called ‘Wetland Friends’ to involve local people in conservation, the team is slowly changing attitudes. Rice growers previously believed that birds were eating their crops and were killing the birds. As a result of an improved understanding of the ecological relationships, and effective communication by the University which has successfully demonstrated that rice cultivation is compatible with avian conservation, the attitude of rice growers and the wider community has changed positively in relation to birds. Instead they recognize the benefits birds bring to their crops. Farmers have also stopped the cutting of mangroves and are pursuing the declaration of the coastal zone as a protected area, whilst community members are engaged in wetland research at the University.
During their research the University team identified two rice paddies with neighboring coastal areas which were proposed as candidates among the Important Bird Areas (IBAs) for Cuba. IBAs are normally located in natural areas, and single-crop cultivation is not what typically comes to mind when one thinks of bird conservation.
Figure 4: Important Bird Areas of Cuba
The first of these proposed IBAs is the Costa Sur de Sancti Spiritus. It encompasses the Sur del Jíbaro, one of the country’s most important rice paddies and a place widely held to host large concentrations of aquatic birds. To the south, it includes a coastal strip of wetlands composed of several important lagoons, such as El Basto and La Limeta, and a strip of mangroves that is several kilometres wide at some points. The area covers about 60,593 ha and 107 species of birds have been recorded there. Numerous migratory species also gather here, especially wading birds and ducks.
Figure 5: IBA Costa Sur de Sancti Spiritus
The second IBA (Humedal Sur de Pinar del Rio) has a similar environment and is located in the south of Pinar del Río province. It includes a group of natural coastal wetlands and the adjacent rice paddies between Los Palacios and Consolación del Sur. The area has more than 101 species of birds, with a notable abundance of aquatic birds, particularly herons and an estimated 20,000 Glossy Ibis (Plegadis falcinellus). There are thought to be more than one hundred of the globally threatened West Indian Whistling-duck (Dendrocygna arborea) in the area.
Figure 6: IBA Humedal Sur de Pinar del Rio
3.2 Main Content of conservation efforts
The possibility that birds may have a positive effect on the rice fields has previously received little attention. The research findings of the team from Ecología de la Universidad de la Havana show that birds are an important biotic component of the rice agroecosystem, especially concerning the energy flow between the paddies and the nearby wetlands. There is a need for farmers and wildlife biologists to work together towards the goal of minimizing rice loss while enhancing the quality of wildlife habitat. Some of the positive effects of birds are:
- The majority of birds in the paddies feed mainly on animal pests and weed seeds rather than rice seeds, and doing so in flooded stubble fields reduces the subsequent crop weeds;
- Waterbirds’ droppings add nutrients to the rice paddies’ soil;
Among the agricultural practices that benefit waterbirds are the avoidance of intermittent flooding or dry cultivation, stubble maintenance during winter, allowing persistence of some weed patches inside fields, and conservation of natural vegetation in rice field areas.
About the study
This study was carried out by the group Ecología de Aves from the Faculty of Biology of the Havana University and financed by the Whitley Fund for Nature under the conservation project titled Rice Paddies and Natural Wetlands as Conservation Sites for Aquatic Birds. We would like to give our special thanks to Susana Aguilar from the National Centre of Protected Areas.
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