Does Long-Term Macrophyte Management in Lakes Affect Biotic Richness and Diversity?

We hypothesize that the richness and diversity of the biota in Lake Moraine (42°50’47”N, 75°31’39”W) in New York have been negatively impacted by 60 years of macrophyte and algae management to control Eurasian watermilfoil ( Myriophyllum spicatum L.) and associated noxious plants. To test this hypothesis we compare water quality characteristics, richness and selected indicators of plant diversity, zooplankton, benthic macroinvertebrates and fish in Lake Moraine with those in nearby Hatch Lake (42°50’06”N, 75°40’67”W). The latter is of similar size and would be expected to have similar biota, but has not been subjected to management. Measurements of temperature, pH, oxygen, conductivity, Secchi transparency, calcium, total phosphorus and nitrites + nitrates are comparable. Taxa richness and the diversity indices applied to the aquatic macrophytes are similar in both lakes. (PDF has 8 pages.)

Angling and species richness of aquatic macrophytes in ponds

Ponds are unjustly neglected habitats. This paper aims to raise awareness of the potential interaction between angling and the macrophyte vegetation of ponds. The work described by the author followed on from a study of 57 ponds in East Yorkshire, northeast England, by Linton & Goulder (2000). They found that the species richness of aquatic vascular plants (macrophytes) is greater in ponds that are used for angling and suggest that to some extent there are more species because disturbance by anglers leads to greater habitat diversity. This article describes how the hypothesis was tested by comparing species richness at fished sites with that at non-fished sites around the margins of ponds in two localities in East Yorkshire. The localities were investigated during August-September 1999.

Bird migration and the spread of Crustacea. [Translation from: Verhandlungen der Deutschen Zoologischen Gesellschaft 27, 311-316, 1963.]

The passive spread of a high percentage of freshwater organisms is one of the most important requirements in short-lived and insular communities for species to attai n and survive - and consequently to balance the lack of a topographical continuity of most inland waters. Unfortunately hardly anything is known about the amounts of seed material typical for any lake into which it is carried. The causes of passive dissemination - wind, water and animals as well as man - are confirmed by many examples. It has been assumed now for at least a hundered years that , among animals, birds play a prominent role, although also disappointingly few facts are at hand. The passage and spread through birds' intestines has up to now been supported only by some limited data. This paper reports on experimental research where the eggs of Daphnia magna, Triops cancriformis, Artemia salina, Diaptomus spinosus and Cypris pubera were introduced by means of gelatine capsules into the oesophagus of a drake. The bird's excrements were inspected under a microscope for eggs and resting stages, and these were transferred into corresponding cultures.

Emerging patterns of species richness, diversity, population density, and distribution in the skates (Rajidae) of Alaska

Six years of bottom-trawl survey data, including over 6000 trawls covering over 200 km2 of bottom area throughout Alaska’s subarctic marine waters, were analyzed for patterns in species richness, diversity, density, and distribution of skates. The Bering Sea continental shelf and slope, Aleutian Islands, and Gulf of Alaska regions were stratified by geographic subregion and depth. Species richness and relative density of skates increased with depth to the shelf break in all regions. The Bering Sea shelf was dominated by the Alaska skate (Bathyraja parmifera), but species richness and diversity were low. On the Bering Sea slope, richness and diversity were higher in the shallow stratum, and relative density appeared higher in subregions dominated by canyons. In the Aleutian Islands and Gulf of Alaska, species richness and relative density were generally highest in the deepest depth strata. The data and distribution maps presented here are based on species-level data collected throughout the marine waters of Alaska, and this article represents the most comprehensive summary of the skate fauna of the region published to date.

A Biogeographic assessment off North/Central California: In support of the National Marine Sanctuaries of Cordell Bank, Gulf of the Farallones and Monterey Bay. Phase II - Environmental setting and update to marine birds and animals

NOAA’s National Centers for Coastal Ocean Science (NCCOS) conducts and supports research, monitoring, assessments, and technical assistance to meet NOAA’s coastal stewardship and management responsibilities. In 2001 the Biogeography Branch of NCCOS partnered with NOAA’s National Marine Sanctuary Program (NMSP) to conduct biogeographic assessments to support the management plan updates for the sanctuaries. The first biogeographic assessment conducted in this partnership focused on three sanctuaries off north/ central California: Cordell Bank, Gulf of the Farallones and Monterey Bay. Phase I of this assessment was conducted from 2001 to 2004, with the primary goal to identify and gather the best available data and information to characterize and identify important biological areas and time periods within the study area. The study area encompasses the three sanctuaries and extends along the coastal ocean off California from Pt. Arena to Pt. Sal (35°-39°N). This partnership project was lead by the NCCOS Biogeography Branch, but included over 90 contributors and 25 collaborating institutions. Phase I results include: 1) a report on the overall assessment that includes hundreds of maps, tables and analyses; 2) an ecological linkage report on the marine and estuarine ecosystems along the coast of north/central California, and 3) related geographic information system (GIS) data and other summary data files, which are available for viewing and download in several formats at the following website: http://ccma.nos.noaa.gov/products/biogeography/canms_cd/welcome.html Phase II (this report) was initiated in the Fall of 2004 to complete the analyses of marine mammals and update the marine bird colony information. Phase II resulted in significant updates to the bird and mammal chapters, as well as adding an environmental settings chapter, which contains new and existing data and maps on the study area. Specifically, the following Phase II topics and items were either revised or developed new for Phase II: •environmental, ecological settings – new maps on marine physiographic features, sea surface temperature and fronts, chlorophyll and productivity •all bird colony or roost maps, including a summary of marine bird colonies •updated at-sea data CDAS data set (1980-2003) •all mammal maps and descriptions •new overall density maps for eight mammal species •new summary pinniped rookery/haulout map •new maps on at-sea richness for cetaceans and pinnipeds •most text in the mammal chapter •new summary tables for mammals on population status and spatial and temporal patterns

Habitat availability and heterogeneity and the Indo-Pacific warm pool as predictors of marine species richness in the tropical Indo-Pacific

Range overlap patterns were observed in a dataset of 10,446 expert-derived marine species distribution maps, including 8,295 coastal fishes, 1,212 invertebrates (crustaceans and molluscs), 820 reef-building corals, 50 seagrasses and 69 mangroves. Distributions of tropical Indo-Pacific shore fishes revealed a concentration of species richness in the northern apex and central region of the Coral Triangle epicenter of marine biodiversity. This pattern was supported by distributions of invertebrates and habitat-forming primary producers. Habitat availability, heterogeneity and sea surface temperatures were highly correlated with species richness across spatial grains ranging from 23,000 to 5,100,000 km2 with and without correction for autocorrelation. The consistent retention of habitat variables in our predictive models supports the area of refuge hypothesis which posits reduced extinction rates in the Coral Triangle. This does not preclude support for a center of origin hypothesis that suggests increased speciation in the region may contribute to species richness. In addition, consistent retention of sea surface temperatures in models suggests that available kinetic energy may also be an important factor in shaping patterns of marine species richness. Kinetic energy may hasten rates of both extinction and speciation. The position of the Indo-Pacific Warm Pool to the east of the Coral Triangle in central Oceania and a pattern of increasing species richness from this region into the central and northern parts of the Coral Triangle suggests peripheral speciation with enhanced survival in the cooler parts of the Coral Triangle that also have highly concentrated available habitat. These results indicate that conservation of habitat availability and heterogeneity is important to reduce extinction and that changes in sea surface temperatures may influence the evolutionary potential of the region.

Assessment of natural resource conditions in and adjacent to Dry Tortugas National Park

This project characterized and assessed the condition of coastal water resources in the Dry Tortugas National Park (DRTO) located in the Florida Keys. The goal of the assessment was to: (1) identify the state of knowledge of natural resources that exist within the DRTO, (2) summarize the state of knowledge about natural and anthropogenic stressors and threats that affected these resources, and (3) describe strategies being implemented by DRTO managers to meet their resource management goals. The park, located in the Straits of Florida 113 km (70 miles) west of Key West, is relatively small (269 square kilometers) with seven small islands and extensive shallow water coral reefs. Significant natural resources within DRTO include coastal and oceanic waters, coral reefs, reef fisheries, seagrass beds, and sea turtle and bird nesting habitats. This report focuses on marine natural resources identified by DRTO resource managers and researchers as being vitally important to the Tortugas region and the wider South Florida ecosystem. Selected marine resources included physical resources (geology, oceanography, and water quality) and biological resources (coral reef and hardbottom benthic assemblages, seagrass and algal communities, reef fishes and macro invertebrates, and wildlife [sea turtles and sea-birds]). In the past few decades, some of these resources have deteriorated because of natural and anthropogenic factors that are local and global in scale. To meet mandated goals (Chapter 1), resource managers need information on: (1) the types and condition of natural and cultural resources that occur within the park and (2) the stressors and threats that can affect those resources. This report synthesizes and summarizes information on: (1) the status of marine natural resources occurring at DRTO; and (2) types of stressors and threats currently affecting those resources at the DRTO. Based on published information, the assessment suggests that marine resources at DRTO and its surrounding region are affected by several stressors, many of which act synergistically. Of the nine resource components assessed, one resource category – water quality – received an ecological condition ranking of "Good"; two components – the nonliving portion of coral reef and hardbottom and reef fishes – received a rating of "Caution"; and two components – the biotic components of coral reef and hardbottom substrates and sea turtles – received a rating of "Significant concern" (Table E-1). Seagrass and algal communities and seabirds were unrated for ecological condition because the available information was inadequate. The stressor category of tropical storms was the dominant and most prevalent stressor in the Tortugas region; it affected all of the resource components assessed in this report. Commercial and recreational fishing were also dominant stressors and affected 78% of the resource components assessed. The most stressed resource was the biotic component of coral reef and hardbottom resources, which was affected by 76% of the stressors. Water quality was the least affected; it was negatively affected by 12% of stressors. The systematic assessment of marine natural resources and stressors in the Tortugas region pointed to several gaps in the information. For example, of the nine marine resource components reviewed in this report, the living component of coral reefs and hardbottom resources had the best rated information with 25% of stressor categories rated "Good" for information richness. In contrast, the there was a paucity of information for seagrass and algal communities and sea birds resource components.

Rapid assessment of stony coral richness and condition on Saba Bank, Netherlands Antilles

The benthic habitats of Saba Bank (17°25′N, 63°30′W) are at risk from maritime traffic, especially oil tankers (e.g., anchoring). To mitigate this risk, information is needed on the biodiversity and location of habitats to develop a zone use plan. A rapid survey to document the biodiversity of macro-algae, sponges, corals and fishes was conducted. Here we report on the richness and condition of stony coral species at 18 select sites, and we test for the effects of bottom type, depth, and distance from platform edge. Species richness was visually assessed by roving scuba diver with voucher specimens of each species collected. Coral tissue was examined for bleaching and diseases. Thirty-three coral species were documented. There were no significant differences in coral composition among bottom types or depth classes (ANOSIM, P>0.05). There was a significant difference between sites (ANOSIM, P<0.05) near and far from the platform edge. The number of coral species observed ranged from zero and one in algal dominated habitats to 23 at a reef habitat on the southern edge of the Bank. Five reef sites had stands of Acropora cervicornis, a critically endangered species on the IUCN redlist. Bleaching was evident at 82% of the sites assessed with 43 colonies bleached. Only three coral colonies were observed to have disease. Combining our findings with that of other studies, a total of 43 species have been documented from Saba Bank. The coral assemblage on the bank is representative and typical of those found elsewhere in the Caribbean. Although our findings will help develop effective protection, more information is needed on Saba Bank to create a comprehensive zone use plan. Nevertheless, immediate action is warranted to protect the diverse coral reef habitats documented here, especially those containing A. cervicornis.