The effectiveness of using carbonate isotope measurements of body tissues to infer diet in human evolution: Evidence from wild western chimpanzees (Pan troglodytes verus)*

Changes in diet throughout hominin evolution have been linked with important evolutionary changes. Stable carbon isotope analysis of inorganic apatite carbonate is the main isotopic method used to reconstruct fossil hominin diets; to test its effectiveness as a paleodietary indicator we present bone and enamel carbonate carbon isotope data from a well-studied population of modern wild western chimpanzees (Pan troglodytes verus) of known sex and age from Taï, Cote d'Ivoire.We found a significant effect of age class on bone carbonate values, with adult chimpanzees being more 13C- and 18O-depleted compared to juveniles. Further, to investigate habitat effects, we compared our data to existing apatite data on eastern chimpanzees (P. troglodytes schweinfurthii) and found that the Taï chimpanzees are significantly more depleted in enamel d13Cap and d18Oap compared to their eastern counterparts. Our data are the first to present a range of tissue-specific isotope data from the same group of wild western chimpanzees and, as such, add new data to the growing number of modern non-human primate comparative isotope datasets providing valuable information for the interpretation of diet throughout hominin evolution. By comparing our data to published isotope data on fossil hominins we found that our modern chimpanzee bone and enamel data support hypotheses that the trend towards increased consumption of C4 foods after 4 Ma (millions of years ago) is unique to hominins

Growth and Survivorship of Scleractinian Coral Transplants and the Effectiveness of Plugging Core Holes in Transplant Donor Colonies

Replicate scleractinian coral transplants were obtained from the species Meandrina meandrites and Montastrea cavernosa on a natural reef, off Dania Beach, Florida, using a hydraulic drill fitted with a 4 in. (~10 cm) core barrel. The transplants were fixed to Reef Ball™ substrates using an adhesive marine epoxy. Drill holes in the donor corals (core holes) were filled with concrete plugs. Control corals, of comparable size to both donor colonies and transplant corals, were monitored for comparison. Transplant corals, donor corals, and controls on the natural reef were monitored for growth and survivorship. Core holes were monitored for tissue regrowth over the surface of concrete plugs. Growth during the transplantation project was defined as an increase in surface area of tissue and skeleton. Growth was monitored on a quarterly basis using photographic techniques. Meandrina meandrites transplants experienced greater mortality and significantly less growth than M. cavernosa transplants. No significant difference in the change in percent tissue coverage between both species of donor corals or between their respective controls was determined. The process of filling core holes in donor colonies with concrete plugs was effective, however, tissue did not completely regenerate over the surface of plugs in either species over the relatively short 15-month observation period. Results of this study indicate that species selection is an important factor in the success of coral transplantation

First-principles investigation of the alloy scattering potential in dilute Si(1-x)C(x)

A first-principles method is applied to find the intra and intervalley n-type carrier scattering rates for substitutional carbon in silicon. The method builds on a previously developed first-principles approach with the introduction of an interpolation technique to determine the intravalley scattering rates. Intravalley scattering is found to be the dominant alloy scattering process in Si1-xCx, followed by g-type intervalley scattering. Mobility calculations show that alloy scattering due to substitutional C alone cannot account for the experimentally observed degradation of the mobility. We show that the incorporation of additional charged impurity scattering due to electrically active interstitial C complexes models this residual resistivity well

Diel Activity Patterns, Space Utilization, Seasonal Distribution and Population Structure of the Yellow Stingray, Urobatis jamaicensis (Cuvier, 1817) in South Florida with Comments on Reproduction.

The yellow stingray, Urobatis jamaicensis is the most common elasmobranch in the coastal waters of Southeast Florida. Despite their common occurrence the ecology of yellow stingrays remains poorly understood. In particular, yellow stingray daily movements, space utilization, seasonal distribution and population structure have not been described. This study was conducted to address the lack of knowledge of these fundamental life history parameters and to provide further information on the ecology of U. jamaicensis in coastal waters of Broward County, Florida. The activity patterns and space utilization of U. jamaicensis were assessed by manual tracking with ultrasonic telemetry. Telemetry tracking of 17 stingrays was conducted from January 1998 to September 2001 with data presented on eight individuals tracked for a full diel cycle (24 h). Tracking data was analyzed with the Animal Movement Analysis Extension (AMAE) in Arcview® GIS to provide graphical representation of observed movements within the complex series of reef terraces and hardbottom communities of Broward County. Bottom topography had considerable influence on the space utilization of stingrays and observed movements varied with location in relation to proximity from the reef edge/sand interface. Movement was intermittent throughout the day, but displayed a highly significant increase during the nocturnal and crepuscular phases in comparison to diurnal movements. Nearly all stingrays demonstrated confined movements and indicated strong site fixity, which may imply the existence of home ranging behavior. The 95% (total 24h activity space) and the 50% (core area) Kernel Utilization Distributions (KUD) were constructed to visually display the shape and size of activity spaces. The data was pooled together for the eight individuals tracked for a full diel cycle and divided into four 6-h shifts. Statistically significant larger activity spaces for both the 95% KUD and the 50% KUD were observed during the nocturnal activity phase. Seasonal distribution was assessed to determine animal residency within the study site and ascertain the occurrence and temporal patterns of onshore/offshore movements. Stationary visual fish census techniques (point counts) from several studies conducted in Broward County from January 1998 to December 2003 were combined to determine the level of abundance across three reef tracts, throughout the entire length of the county. Data was tested for monthly and seasonal differences and for variation between reefs. Analysis of seasonal distribution established population residency is year-round with no indication of offshore emigration associated with a temperature preference. Population structure analyses were conducted to determine the sex ratio and size distribution of U. jamaicensis to examine any potential gender segregation or ontogenetic partitioning. The sex ratio was compared for differences monthly, seasonally and between reefs for expected vs. observed frequencies. Only spring observations (March, April, May) evidenced a statistically significant difference from a 1:1 ratio, where females dominated the inshore observations 20F:8M. Average size of both genders was 333mm TL, however, females dominated the larger size classes (\u3e350mm TL). Few neonates were observed during this study with most observations occurring in shallow inshore water (depth), suggesting a nearshore nursery. Increased abundance and presence on the offshore reef among intermediate size classes (250-299mm to 300-349mm) suggests a potential ontogenetic shift to deeper water. Observations on the seasonal patterns of the reproductive condition of female yellow stingrays are also provided

A second assessment of the stock of megrim Lepiodorhombus whiffiagonis in Divisions Vll b, c, j and k

An assessment of megrim captured by Irish and joint venture (Spanish) vessels in Divisions Vll b, c, j, k is based on landings from both fleets and discards from Irish vessels targeting whitefish and Nephrops. Fishing activity by the joint venture fleet is centred on the 200m depth contour. Megrim CPUE has declined since 1985. Lepidorhombus whiffiagonis constitutes the majority of the landings by joint venture vessels; L. boscii amounts up to 2% by weight of the landings from deeper waters. In catches of undersized megrim, L. boscii was 12% of the total. Landings of L. whiffiagonis have similar length frequency distributions in the Irish inshore and joint venture fleets. There are indications of what may be seasonal abundance in the discards and landings of Irish vessels fishing inshore. Discards were calculated as 77% of landed weight in the first half of the year and 31% in the second. Megrim with an inshore provenance were slightly larger than those coming from deeper waters. The following growth parameters were calculated: L∞ = 51.2cm, k = 0.17 and to = -0.97. A catch curve derived from the combined landed and discarded megrim has a value of Z = 0.45, slightly less than the value calculated for the inshore Irish fleet (0.49). F is consequently in much the same position as in the 1989-90 assessment, on the negative slope of the yield per recruit curve.Funder: Marine Institut

The exploitation of angler fish Lophius Spp. in Irish waters

Two species of European angler, Lophius plscatorius and L. budegassa occur In Irish waters. L piscatorius is dominant, particularly closer to the coast; L. budegassa becomes more important moving south and in landings from medium/deep water. Three stocks of anglers are recognized; this work concerns the fish in the central one, specifically in ICES Divisions Vllb, c and j,k. Anglers are taken in a mixed demersal fishery, and they are particularly associated with hake and megrim. Most landings of the species come from ICES Divisions VlIg-k. The species have traditionally been taken in a mixed demersal fishery, mainly by France and Scotland. Ireland's landings have increased from 100t in 1977 to in excess of 2,000t in recent years. Species composition of the landings was determined by port sampling. The proportion of Lophius piscatorius, while still dominant, has declined since the mid 1980s. A short CPUE time series from joint venture vessels fishing medium/deep water (approximately 200 m) shows no consistent trends although the values for 1991 were the lowest in the six years. Irish vessels take anglers of slightly greater weight than do their joint venture (Spanish) counterparts. Length frequency distributions of both species from the Irish trawl fishery are available from 1987 to 1991 inclusive. They are redistributed by age using French ALKs. The age distribution shows no particular trend for L. budegassa whereas that for L. piscatorius shows evidence of strong year classes from the mid 1980s passing through the population. The sharp reduction in angler CPUE in 1991 may have resulted from the exhaustion of strong mid 1980s year classes of L. piscatorius. A large plus group in the age distribution of L. piscatorius restricted interpretation of its population structure. Discarding of anglers appears to be very low in the south western Irish trawl fisheries, an estimate of 6.8% landed weight being used in this assessment. A catch curve for L. piscaforius suggested a value of Z+0.48; taking M=0.15 provides a value for F=0.33, to the right of Fmax and in general agreement with what has been concluded for this species in recent assessments

Aspects of the exploitation of hake Merluccius merluccius belonging to the northern stock by fleets based in Ireland

The development of the hake fishery in the ICES Divisions adjoining Ireland displays strong similarities to the fishery for megrim; Ireland's landings of hake rose from 100t per year in 1979 to 2,000t ten years later. Most hake comes from Divisions Vllg-k. The Communities Logbook of the Irish-Spanish joint venture fleet provides a short time series. CPUE by both demersal trawl and long line declined sharply between 1985 and 1991. The second quarter is the most productive of hake landings but otherwise there is no clear seasonal pattern. Hake were sampled on a half yearly basis and the fish were aged on the otoliths with a success rate of 70%. Ages in the first half were adjusted to a birth date of 1 January. Mean lengths at age were higher than those calculated by statistical methods (Normsep.). Length frequencies indicated two age groups in the discards. Methods of capturing hake have altered over the past five years, gill nets have increased their share of the Irish catch and, in 1991, were a close second to demersal trawl. Age of recruitment to the landings is 2-4 years. Discard hake was calculated at 25-163% by weight of landings per quarter in 1991, higher values coming from small-meshed nets targeting Nephrops. Survivorship curves based on aged length frequencies of hake taken by whitefish boats provided F values of between 0.40 and 0.76. These results are high and together with sharply declining CPUE would seem to suggest the part of the stock in Divisions Vllb-c and Vllg-k is more heavily fished than the stock in other parts of Sub-area VII.Funder: Marine Institut

The post-peak-yield gill-net fishery for spurdog Squalus acanthias L. in Western Ireland

A gill net fishery, directed on Spurdog, expanded rapidly on the western coast of Ireland in the 1980s and quickly collapsed, the fishermen moving offshore in pursuit of smaller individuals. Catch per effort and landing data in the gill net fishery are used to estimate the size of the mature and maturing component of the south western "stock" which is within a range of 3,700 tonnes (landed) and 5,700 (calculated). An appraisal of the post-peak-yield landings reveals that the average individual weight declined from those of peak landings, in males by 9.5% and females 32.0%, and the percentage of females in them declined from 75 to 19%. The majority of the later catches were immatures whereas the peak-yield catches were mainly mature and maturing females. The average age of females was reduced from 19 to 16 years - 18 to 17 years in the case of males - and later captures were a shorter length at age. The fate of the depleted stock is not known and the possibility of its locus having moved elsewhere cannot be discounted

Catch Per Unit Effort by the Joint Venture (Irish-Spanish) Fleet from 1985 to 1992

The formation in 1979 of the joint venture (Irish-Spanish) fishing fleet, Eiranova, introduced to the industry in Ireland a range of target species and fishing grounds on which the Irish demersal fishery has subsequently expanded. From the second quarter of 1985 the European Communities' Logbook has provided a format on which landings and details of fishing effort have been recorded. This leaflet reviews the catches of various species per effort expended by joint venture demersal trawl and long-lining vessels for the eight years documented by the Logsheets. The high value components of the trawl fishery are the prime fish (hake, monkfish and megrim) which are exported fresh to Spain. Hake is the principal target of long-liners. The fishery is concentrated in ICES statistical Divisions VIIb and VIIj. Since 1985, the CPUE of all species has declined by 39% and the trend in prime fish landings runs in parallel with this, mainly because of the reduction in hake landings. CPUE indices for all other species which are consistently recorded are given. Some comparisons are made among CPUE indices in Divisions VIlb, j and adjoining areas. However, these indices depend much on the exploited size range of a target species and the area in which fishing effort is concentrated and the bulk of the data are presented without further comment. A brief glossary of Spanish terminology is appended