Effect of Cattail (Typha domingensis) Extracts, Leachates, and Selected Phenolic Compounds on Rates of Oxygen Production by Salvinia (Salvinia minima)

Salvinia (Salvinia minima Willd.) is a water fern found in Florida waters, usually associated with Lemna and other small free-floating species. Due to its buoyancy and mat-forming abilities, it is spread by moving waters. In 1994, salvinia was reported to be present in 247 water bodies in the state (out of 451 surveyed public waters, Schardt 1997). It is a small, rapidly growing species that can become a nuisance due to its explosive growth rates and its ability to shade underwater life (Oliver 1993). Any efforts toward management of salvinia populations must consider that, in reasonable amounts, its presence is desirable since it plays an important role in the overall ecosystem balance. New management alternatives need to be explored besides the conventional herbicide treatments; for example, it has been shown that the growth of S. molesta can be inhibited by extracts of the tropical weed parthenium (Parthenium hysterophorus) and its purified toxin parthenin (Pande 1994, 1996). We believe that cattail, Typha spp. may be a candidate for control of S. minima infestations. Cattail is an aggressive aquatic plant, and has the ability to expand over areas that weren't previously occupied by other species (Gallardo et al. 1998a and references cited there). In South Florida, T. domingensis is a natural component of the Everglades ecosystem, but in many cases it has become the dominant marsh species, outcompeting other native plants. In Florida public waters, this cattail species is the most dominant emergent species of aquatic plants (Schardt 1997). Several factors enable it to accomplish opportunistic expansion, including size, growth habits, adaptability to changes in the surroundings, and the release of compounds that can prevent the growth and development of other species. We have been concerned in the past with the inhibitory effects of the T. domingensis extracts, and the phenolic compounds mentioned before, towards the growth and propagation of S. minima (Gallardo et al. 1998b). This investigation deals with the impact of cattail materials on the rates of oxygen production of salvinia, as determined through a series of Warburg experiments (Martin et al. 1987, Prindle and Martin 1996).

1979 Ecological study of fishes and the water quality characteristics of Florida Bay, Everglades National Park, Florida

Fish collections under varying ecological conditions were made by trawling and seining, monthly and quarterly in depths of <1 m to depths of 3 m of the Florida Bay portion of Everglades National Park, Florida. From May 1973 through September 1976, a total of 182,530 fishes representing 128 species and 50 families were taken at 27 stations. An additional 21 species were identified from sportfish-creel surveys and supplemental observations. Most of the species collected were juveniles of species that occur as adults in the Florida Bay creel census survey, or were small species that were seasonal residents. Marked temporal and spatial abundance of the catches was observed. The greatest numbers and biomass of the fishes occurred in the wet season (summer/fall), whereas lowest numbers and biomass appeared during the dry season (winter/spring) The greatest abundance and diversity of fishes was found in western Florida Bay followed by eastern and central Bay regions respectively. Overall, five species comprised 75% of the numerical total while eleven species made up 75% of the total biomass. Collections were dominated numerically by anchovies (Engraulidae), especially Anchoa mitchilli, in western Florida Bay. Mojarras (Gerridae), mostly silver jenny Eucinostomus gula, and porgies (Sparidae), especially pinfish Lagodon rhomboides, dominated numerically in central and eastern portions of the Bay, respectively. Except for salinity, other measured physico-chemical parameters (water temperature, pH, dissolved oxygen, and turbidity) showed no variation beyond ranges considered normal for shallow, tropical marine environments. Salinity varied from 0 to 66 ppt near the mainland. Nearshore hypersaline conditions (>45 ppt) persisted for nearly 2 years during the 1974 - 1975 severe drought period. Significant reductions in fish abundance/diversity were observed in relation to hypersaline conditions. Bay-wide macrobenthic communities were mapped (presence/absence) and were primarily comprised of turtle grass (Thalassia), shoalgrass [(Diplanthera = (Halodule)], and/or green algae Penicillus. Seasonal dieoff of seagrasses was observed in north-central Florida Bay. (PDF contains 107 pages)

The decline in the commercially important species of fish and predominance of Clarias lazera in Lake Chad

About 86 species of fish have been recorded in the Lake Chad. Most of the species occurring in the lake are widespread including most of the commercially important species. Fish distribution in the lake was adversely affected by the 1972/73 and 1983/84 droughts. The commercially important species before the 1972/73 drought were; Lates, Labeo distichodus, Heterotis, Gymnarchus, Hydrocynus, Citharinus and Bagrus. Other species which had less commercial value at that time include, Clarias, Gnathanemus, Polypterus, Protopterus, Tilapia and Synodontis. Lates niloticus was the most predominant species of commercial importance comprising 50-60% of the total catches of fishermen between 1962 and 1973. Before the 1972/73 drought, occurrence of Clarias lazera was negligible and restricted to long line catches and had little commercial value. As a result of the drought of 1972/73 which resulted in near drying up to the northern sector of the lake, fish populations were confined to isolated pools and were completely scooped out. The remaining fish populations retreated to the southern basin where enough water always remained to hold the surviving representatives of the population. The effects of the drought resulted in occurrence of the little known C. lazera along with other hardy species like Tilapia and Protopterus to dominate the existing fish species composition. In 1976, C. lazera dominated the total catches of fishermen with 85.6%. An overview of the fish population in the lake, their relative abundance, changes in species composition, the effects of drought on the fauna of the lake based on the available data are discussed in this paper

Some experiments on commercial pond fish culture in the tidal mangrove area of Niger delta of Nigeria

A pilot fish culture project was initiated by Shell Petroleum Development Company of Nigeria Limited in 1981 with specific aims and objectives. Site selection, survey, pond construction method and fish production with regards to experiences gathered and gained, problems and solutions so far obtained are discussed. Trials of freshwater fish species to check their adaptability to brackishwater ponds were carried out and the promising results of the growth rate of these species when compared with the traditional local brackishwater species selected for culture are reported. The extension programme so far carried out is briefly described

Utilization of non-piscine pituitary extract in the breeding of Clarias gariepinus

The use of synthetic and non-synthetic hormones have been reported in different regions with the recommendation of different doses. The adaptability of these findings have however not been very successful due to the high cost of building and maintaining hatchery, high cost of synthetic hormone (when available) and high level manpower required. It is obvious that adaptive research in the past ten years in developing countries like Nigeria have been geared towards utilization of resources that are equally effective but cheap and ready to come by. This paper reports the utilization of the pituitary extract of bull frog (Rana adspersa) and the toad (Bufo regularis) in the induced breeding of the African catfish, Clarias gariepinus. The extraction and dosage are discussed alongside the preliminary rearing of fries in outdoor hatchery tanks. Human chorionic gonadotrophin (HCG) and Clarias pituitary extracts were used as control

The past history and present trends in the fisheries of Lake Chad

Lake Chad is a very large, shallow eutrophic lake shared by Chad, Nigeria, Niger and Cameroun. It supplies approximately 13% of Nigeria's inland fish. It however lies in an unstable ecological environment characterised by intermittent period of rainfall and drought. This creates a very large draw down area. Consequently, the fisheries are affected by the oscillation in the size of lake due to the drought. Other factors affecting the volume of water are the numerous dams on the inflow rivers. The fishery is also subjected to intense overfishing and may be affected by pollution and other land use practices. The paper discusses changes that took place over the years as a result of the factors of drought, effect of dams on the inflow rivers. The fishery is also subjected to intense overfishing and may be affected by pollution and other land use practices. The paper discusses changes that took place over the years as a result of the factors of drought, effects of dams and overexploitation. Previous records of fish production, species composition and distribution, the status of the fish stocks, their sizes are compared with more recent data. The status of the fishery before and after the contraction of the lake is discussed. Suggestion for a national exploitation of the lake based on habitat improvement, increasing the volume of the water in the lake through controlled use of the influent rivers as well as reduction in overfishing are made

Panama City Fisheries Resources Office: FY 2008 Annual Report

HIGHLIGHTS FOR FY 2008 1. Completed the first of a two-year Gulf sturgeon population study on the Choctawhatchee River, Florida. The sub adult and adult Gulf sturgeon population was estimated at 2,800 fish. 2. Gulf sturgeon eggs were collected at three hard bottom sites in the Apalachicola River, Florida; two sites were previously confirmed spawning areas and one was a newly confirmed spawning area. 3. Documented 55 potential environmental threats to Gulf sturgeon spawning habitat in the Pea River, Florida and Alabama. 4. Assigned the Eglin AFB Road-Stream Crossing Working Group to guide the closure, repair and maintenance of roads and road stream crossings that impact threatened and endangered species. 5. Conducted 81 assessments of fish and stream invertebrates on and in watersheds surrounding Eglin AFB. 6. Provided technical support for the 5-year status review and reclassification proposed rule for the Okaloosa darter. 7. Initiated an intensive population genetic analysis of the Okaloosa darter throughout its range. Tissues from over 200 Okaloosa darters were collected and analyzed. 8. Established a GIS database to serve as a host for data from any sites sampled for mussels in Northeast Gulf of Mexico drainages. 9. Conducted habitat surveys at 115 locations in the Apalachicola River to assess the effects of drought-related mussel mortality and strandings, evaluate habitat conditions, and assess population demography. 10. A land use/aerial imagery threats assessment data analysis was completed for the Chipola River. A total of 266 impoundments/borrow pits and 471 unpaved road crossings were identified among the threats. 11. Okaloosa darters marked with elastomeric dyes were monitored in Mill Creek, Eglin AFB, to determine movement and habitat use following completion of a fish passage project. 3 12. Partners for Fish and Wildlife funded a streambank and riparian restoration project on Econfina Creek consisting of 3,900 feet of streambank fencing to exclude cattle access. One acre of riparian floodplain was planted with native trees. 13. We provided design and on-the-ground assistance for restoring surface hydrology at St. Vincent NWR. The project restored approximately 1.5 miles of tidal stream and 100 acres of wetlands. 14. A study was completed on 11 coastal streams to document large wood debris relationships with fluvial geomorphic characteristics. 15. We developed a Population Viability Analysis model for the fat threeridge mussel to determine current and future risk of extinction. 17. A Gulf Sturgeon Friends Group, “Gulf Sturgeon Preservation Society” was organized in FY 08. 18. Multiple outreach projects were completed to detail aquatic resource conservation needs and opportunities, including National Fishing Week, Earth Day, several festivals and school outreach.

Panama City Fisheries Resources Office: FY 2007 Annual Report

HIGHLIGHTS FOR FY 2007 1. Completed a three-year Gulf sturgeon population study on the Escambia River, Florida. The population was estimated at 451 fish. 2. Implemented the Gulf Striped Bass Restoration Plan by coordinating the 24th Annual Morone Workshop, leading the technical committee, transporting broodfish, coordinating stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system, and evaluating post-stocking success. 3. Completed a survey to document the extent of aquatic resources, recreational fishing opportunities, and fishery management needs on Department of Defense (DoD) facilities located in Region 4. 4. Continued a project in the Apalachicola River to describe the effects of exceptional drought conditions on freshwater mussel recovery. 5. Initiated a study to locate extant populations of the federally endangered Ochlockonee moccasinshell in the Ochlockonee River Basin. We documented the first live individuals in 14 years. 6. Completed a five-year status review for seven threatened and endangered freshwater mussels in the NEG drainages. 7. Restored Mill Creek to improve habitat for the endangered Okaloosa darter by removing six fish passage barriers and creating approximately 3,000 linear feet of new and regenerated stream channel with floodplain and native vegetation. 8. Completed a fish passage project that connected about 5 miles of habitat in Little Rocky Creek, Eglin Air Force Base, to benefit the Okaloosa darter. 9. Completed a threats analysis to aquatic species in the Chipola River watershed using GIS stream data, aerial imagery, and land cover data. 10. Multiple outreach projects were completed to detail aquatic resource conservation needs and opportunities, including National Fishing Week, Earth Day, several festivals, and school outreach.

Panama City Fisheries Resources Office: FY 2006 Annual Report

HIGHLIGHTS FOR FY 2006 1. Captured and tagged 475 Gulf sturgeons in five Florida rivers and one bay. 2. Documented Gulf sturgeon marine movement and habitat use in the Gulf of Mexico. 3. Assisted the National Oceanic and Atmospheric Administration (NOAA) with the collection of Gulf sturgeon, implantation of acoustic tags, and monitoring of fish in a study to examine movement patterns and habitat use in Pensacola and Choctawhatchee bays post-Hurricane Ivan. 4. Provided technical assistance to Jon “Bo” Sawyer in completing a study – Summer Resting Areas of the Gulf Sturgeon in the Conecuh/Escambia River System, Alabama-Florida – for acquiring a Degree of Master of Science at Troy University, Alabama. 5. Coordinated tagging and data collection with NOAA observers aboard trawlers while collecting Gulf sturgeon during dredging operations in the coastal Gulf of Mexico. 6. Hosted the 7th Annual Gulf Sturgeon Workshop. 7. Implemented Gulf Striped Bass Restoration Plan by coordinating the 23rd Annual Morone Workshop, leading the technical committee, transporting broodfish, coordinating the stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system, and evaluating post-stocking success. 8. Continued updating and managing the Freshwater Mussel Survey Database, a Geographic Information System (GIS) database, for over 800 unique sites in the Northeast Gulf (NEG) drainages in Alabama (AL), Georgia (GA), and Florida (FL). 9. Formed a recovery implementation team for listed mussels in the ACF river basin and oversaw grant cooperative agreements for 14 listed and candidate freshwater mussels in the NEG watersheds. 10. Initiated a project in the Apalachicola River to relocate mussels stranded as a result of drought conditions, and calculate river flows at which mussels would be exposed. 11. Initiated a project in Sawhatchee Creek, Georgia to determine the status of threatened and endangered (T&E) freshwater mussels and target restoration projects, population assessments, and potential population augmentation to lead toward recovery of the listed species. 12. Initiated a study to determine the age and growth of the endangered fat threeridge mussel (Amblema neislerii). 13. Provided technical assistance to the Panama City Ecological Services office for a biological opinion on the operations of Jim Woodruff Lock and Dam and its effects on the listed species and designated and proposed critical habitat in the Apalachicola River, Florida. 14. Assisted with a multi-State, inter-agency team to develop a management plan to restore the Alabama shad in the ACF river system. 15. Conducted fishery surveys on Tyndall AFB, Florida and Ft. Benning, Georgia and completed a report with recommendations for future recreational fishery needs. 16. Provided fishery technical assistance to four National Wildlife Refuges (NWR) (i.e., Okefenokee NWR, Banks Lake NWR, St. Vincent NWR, and St. Marks NWR). 17. Initiated an Aquatic Resources and Recreation Fishing Survey on Department of Defense facilities located in Region 4. 18. Identified 130 road-stream crossings on Eglin AFB for rehabilitation and elimination of sediment imputs. 19. Continued the Aquatics Monitoring Program at Eglin AFB to assess techniques that determine current status and sustainability of aquatic habitat and develop a measure to determine quality or degradation of habitat. 20. Assisted Eglin AFB Natural Resource managers in revising the installation’s Integrated Natural Resources Management Plan (INRMP) and its associated component plans. 21. Coordinated recovery efforts for the endangered Okaloosa darter including population/life history surveys, stream restoration, and outreach activities. 22. Initiated a comprehensive status review of the Okaloosa darter with analyses performed to assess available habitat, preferred habitats, range expansions/reductions/fragmentations, population size, and probability of extinction. 23. Assisted the Gulf Coastal Plain Ecosystem Partnership and the Florida Fish and Wildlife Conservation Commission (FWC) under a Memorandum of Agreement to develop conservation strategies, implement monitoring and assessment programs, and secure funds for aquatic management programs in six watersheds in northwest Florida and southeast Alabama. 24. Entered into a cooperative agreement with the U.S. Air Force to encourage the conservation and rehabilitation of natural resources at Hurlburt Field, Florida. 25. Multiple outreach projects were completed to detail aquatic resources’ conservation needs and opportunities; including National Fishing Week, Earth Day, several festivals, and school outreach.

Adaptation of coastal communities in the Philippines to the impacts climate change

The Quedan and Rural Credit Guarantee Corporation (Quedancor) of the Philippine Department of Agriculture has the critical responsibility of providing and improving credit assistance to fishers, it also has the task of helping its beneficiaries meet the repayment obligations of their loans. One reason for defaults can be attributed to the devastating impact of natural calamities. Schemes in place are still insufficient to help safeguard lending programs and operations from non-repayment of loans due to production losses and damages to personal properties.(PDF contains 5 pages) Natural calamities include the uncertainties and vagaries of weather and climate that bring about typhoons, floods, and drought; earthquakes; volcanic eruption as well as pests and diseases that affect the productivity of fisheries. When natural calamities occur, small fishers are unable to pay their loans from Quedancor, moreover they have difficulty renewing their loan applications from Quedancor or accessing credit from other sources. Failure to access credit could disable them to continue venture on fishing activities and could eventually jeopardize the welfare of their entire household. The inability of creditors to pay their loans and meet their obligations also impair, to a large extent, the financial operation and viability of the lending institutions. Risk management schemes currently employed include price stabilization measures, targeted relief` to typhoons and drought victims, and crop insurance systems, to name a few. Some of these schemes are becoming very expensive to implement. Moreover, they fail to enable fishers regain sufficient resources so that they may continue production.

The importance of periodic droughts for maintaining diversity in the freshwater environment

Whereas some species may rely on periodic drought conditions for part of their life histories, or have life strategies suited to exploiting the habitat or changed environmental conditions that are created by drought, for other organisms it is a time of stress. Periodic drought conditions therefore generate a series of waves of colonization and extinctions. Studies on lowland wet grassland, in winterbournes and in the toiche zone of both ponds and rivers, also demonstrate that different organisms are competitively favoured with changing hydrological conditions, and that this process prevents any one species from overwhelming its competitors. Competitive impacts may be inter- and intraspecific. It is therefore apparent that the death of organisms such as adult fish during severe drought conditions, though traumatic for human onlookers and commercial interests, may be merely a regular occurrence to which the ecosystem is adapted. The variability of climatic conditions thereby provides a direct influence on the maintenance of biological diversity, and it is this very biodiversity that provides the ecosystem with the resilience to respond to environmental changes in both the short and the longer term.

Rapid changes in the vegetation of a shallow pond in Epping Forest, related to recent droughts

Over much of Britain, 1995 and 1996 have been perceived as drought years. To evaluate the impact that local climatic conditions are having upon successional changes in higher vegetation (macrophytes), Speakmans Pond in Epping Forest was surveyed and mapped in 1996. The results are related to previous vegetation surveys carried out in 1989 and 1991. In 1989 the dominant marginal vegetation was floating sweet-grass Glyceria fluitans, which also covered a major part of the main body of the pond. Other abundant species included soft rush Juncus effusus, reed mace Typha latifolia and yellow flag Iris pseudocorus. A small (central) area of open water contained bladderwort Utricularia vulgaris and white water-lily Nymphaea alba. A similar plant coverage was found in 1991, with a dominance of floating sweet-grass along the shallow eastern edge. A marked change in the pond was found during the 1996 survey of vegetation in July, when the pool was dry. The major plant cover now consisted of creeping bent Agrostis stolonifera, with isolated clumps of Yorkshire fog Holcus lanatus around the edges; both are terrestrial grasses found on land surrounding the pond. Rushes (Juncus) had increased their distribution round the margins of the pond, and the patch of yellow flag noted in 1989 and 1991 was not found in 1996. The deeper trenches were also dry, but a small patch of white water-lily remained adjacent to one of the trenches.

Plant nutrients and major ions in the Little Sea, Studland, Dorset

This short paper records some measurements made on the Little Sea, a shallow, coastal, acidic lake on Studland Heath, Dorset. The lake, formed about 100 years ago by dunes cutting off a sea inlet, has not received any input of agricultural fertilizers or other waste products for at least the last 30 years. It is a Site of Special Scientific Interest (SSSI). Samples of surface water were taken from the northern and southern ends of the lake at 3-monthly intervals, from July 1995 to April 1996. The first samples in July 1995 were taken during a period of drought; rain, sometimes very heavy, came in late September. With the exception of silicate, potassium and phosphate, there were no large changes in plant nutrient concentrations during the year. The concentration of nitrate-nitrogen was very low (close to the limits of analytical detection), but total phosphorus at ca. 30 mu g per litre was similar to concentrations found in some of the Cumbrian eutrophic lakes. The large number of algal species at low cell/colony concentrations suggested that the lake is mesotrophic. Sodium, chloride and magnesium in the lake water were close to the same proportions as those found in sea water. Dry and wet deposition of sea-salts on the lake surface and its catchment area probably is the major source of sodium, magnesium and chloride ions in the lake, and also accounts for about half of the mean potassium and sulphate concentrations.

Simulations of phytoplankton dynamics in El Gergal Reservoir, Southern Spain (PROTECH)

The Mediterranean region is characterised by a variable climate with most of the rain falling during the winter and frequent summer droughts. Such warm, dry periods are ideal for the growth of large algal blooms that often consist of potentially toxic Cyanobacteria. This makes the management of water for human use particularly challenging in such a climate and it is important to understand how such blooms can be avoided or at least be reduced in size. PROTECH (Phytoplankton RespOnses To Environmental CHange) is a model that simulates the dynamics of different species of phytoplankton populations in lakes and reservoirs. Its distinct advantage over similar models is its ability to simulate the relative composition of the algal flora, allowing both quantitative and qualitative conclusions to be drawn e.g. whether Cyanobacteria could be a potential problem. PROTECH has been applied primarily to lakes and reservoirs in northern Europe. Recently, however, the model has been applied to water bodies in lower latitudes, including Australia to a water supply reservoir in the south of Spain, El Gergal. El Gergal is the last in a chain of reservoirs that supply water to the city of Seville. It was brought into service in April 1979 and has a maximum storage volume of 35 000 000 m3. This article summarises the application of PROTECH in order to simulate the following problems: • the effect of a large influx of Ceratium biomass into El Gergal from another reservoir • the effect of using alternative water sources instead of the Guadalquivir River (used occasionally to raise water levels in El Gergal) • the effect of installing tertiary sewage treatment on the Cala River • the effect of simulated drought conditions on phytoplankton in the reservoir.

Comparison of permanent and temporary streams of calcareous Provence [Translation from: Annales de Limnologie 9(3) 273-292, 1973]

The rainfall regime and the karstic nature of the subsoil determines the alternation of a period of flow and a period of drought for a large number of Mediterranean streams. Amongst this type of stream it is possible to distinguish temporary streams, characterised by a period of flow for several months permitting the establishment of the principal groups of aquatic insects; and ephemeral streams whose very brief period of flow permits the establishment of a community reduced to a few species of Diptera. This paper aims to study the structure of the communities which colonise this particular type of stream and the ecology of the principal species which constitute these communities. Four French temporary streams were examined and temperature regimes, dissolved oxygen, calcium and magnesium measured. Samples of fauna were taken regularly and the biotic composition established. The analysis of similarities between the three permanent streams are discussed and compared with permanent streams.