Importance of the upper estuary as a nursery ground for fishes in Ariake Bay,Japan

To examine the importance of the upper estuarine areas of Ariake Bay as a nursery ground for fish, assemblages of larvae and juveniles were compared among various aquatic habitats. The upper estuaries of the bay (the Rokkaku and Hayatsue estuaries) are brackish, highly turbid waters with high tidal velocities, and differ substantially from the Isahaya area, which has been separated from the bay by a man-made dike, to the middle estuary (the Kikuchi estuary). Abundances of larvae and juveniles were higher in the estuaries than in the open bay and Isahaya areas. Abundant species in the upper estuaries were similar to each other, but differed from those of the middle estuary. This was primarily due to larvae and juveniles of fishes that occurred almost entirely in the upper estuaries, such as Acanthogobius hasta, Boleophthalmus pectinirostris, Coilia nasus, Cynoglossus abbreviatus, Nibea albiflora, Odontamblyopus lacepedii, Trachidermus fasciatus and Tridentiger barbatus. These results suggest that the upper estuaries play an important role as nursery grounds for fishes.     

Winter growth of juvenile plaice on the Port Erin Bay (Isle of Man) nursery ground

Juvenile plaice ( Pleuronectes platessa ) were studied in Port Erin Bay, Isle of Man, U.K. between September and March 1989/1990 and 1990/1991. Plaice (>90 mm) were tagged and individual growth rates calculated for the autumn, winter and over-winter time periods. During the study the population of fish >90 mm remained fairly stable both within a study season and between years. Autumn growth rates ranged from 0 to 0.39 mm day⁻¹ (mean₁₉₈₉=0.13 mm day⁻¹, mean₁₉₉₀=0.10 mm day ⁻¹) and winter 0 to 0.5 mm day⁻¹ (mean₁₉₉₀=0.11 mm day⁻¹ and mean₁₉₉₁=0.17 mm day ⁻¹). In general, growth rates were higher at higher mean seasonal temperatures. However, relative growth rate was significantly higher in the colder winter period of 1991 than 1990.     

Blood glucose in marine penaeid prawns: I. Neuroendocrine regulation in Parapenaeopsis hardwickii (Miers). (Crustacea,Decapoda, Penaeidae)

In the present investigation on femaleP. hardwickii, the blood glucose level in bilateral eyestalk extirpated, reinjected with ES extract as well as normal prawns, administered with ES, different concentrations of BR and ThG extracts, was estimated quantitatively after fifteen minutes and two hours. During all treatments there was an immediate hike in blood glucose level after fifteen minutes but after 24 hr. of eyestalk ablation the level does not differ significantly (P > 0.05) from controls. There was a significant (P < 0.01) enhancement in blood glucose level in the cauterized eyestalkless and normal prawns injected with ES extract after 2 hr. There was a considerable (93% level of confidence) decrease in blood glucose level of normal prawns after injecting higher concentrations of BR and ThG extracts. There was an obvious change in blood glucose level due to the endocrine hormones injected from other prawns of the related family. ES extracts ofP. stylifera produced a significant (P < 0.01) increase, whereas higher concentration of BR and ThG extracts caused considerable (92% level of confidence) decrease in blood glucose level after injecting in cauterized eyestalkless prawns. The extracts of the same endocrine centres fromMetapenaeus monocerus did not induce any significant (P > 0.05) alteration in blood glucose quantity ofP. hardwickii. Hence from the above findings it may be inferred that, the hormones produced by eyestalks (X organ-Sinus gland Complex) posses a hyperglycemic factor, whereas hormones released from BR and ThG might be having a property to cause hypoglycemia (?).     

0-group flatfish growth conditions on a nursery ground (Bay of Canche, Eastern English Channel)

The settlement and growth conditions of three 0-group flatfish species, sole (Solea solea L.), plaice (Pleuronectes platessa L.) and dab (Limanda limanda L.) in the Bay of Canche, French coast of the Eastern English Channel, were investigated during summer 1997. 0-group dab were the more abundant of the three species (75.4%) followed by plaice (21%) and sole (3.6%). Analyses of fish size distribution indicated that settlement of plaice occurred before sole and dab. Growth of sole was faster than that of plaice, which in turn was faster than that of dab (0.68, 0.43 and 0.33 mm d^?1 respectively). Sole differed from plaice and dab by their larger mean length attained at the end of their first summer stay in the nursery ground. Growth performances of 0-group sole and plaice were analysed by comparing estimated growth in the field with predicted maximum growth according to temperature-growth rate models from experimental studies of growth with unlimited food supply. The data of this study suggest that plaice growth may have been limited during late summer, whereas sole growth does appear to have been determined only by water temperature.     

Southern right whales (Eubalaena australis) return to a former wintering calving ground: Fowlers Bay,South Australia

Southern right whales (SRW), Eubalaena australis, have reoccupied historically important winter habitat ranges (calving grounds) in recent years along the southern Australian coast. Here we present findings of increased abundance of SRW at Fowlers Bay, South Australia, a previous shore‐based whaling station. This study investigates: SRW inter‐ and intraseasonal trends in relative abundance; changes to the relative proportion of the southwestern subpopulation represented by SRW at Fowlers Bay; distribution; and occupancy. Sighting and photo identification data were collected during annual aerial (1993–2016) and vessel surveys (2014–2016). The total number of female and calf pairs was 3 during 1993–2003 and 63 during 2004–2014. Despite high variability in annual relative abundance, the rate of mean increase from 1993 to 2016 (29.0%/yr, 95% CI = 0, 54.2) exceeded the maximum biological rate for the species (6%–7%/yr). Peak relative abundance was recorded in July and August. SRW at Fowlers Bay represent an increasing proportion of the southwestern subpopulation (range = 0.9%–7.4%). Mean occupancy was 23 d (range = 1–75) for female and calf pairs and 2 d (range = 1–15) for unaccompanied adults. Reduced sightings in 2015 and 2016 demonstrate plasticity in SRW abundance at Fowlers Bay. Research into the movement and connectivity of SRW is needed to understand drivers of habitat dispersal in Australia.     

The importance of mangroves, mud and sand flats, and seagrass beds as feeding areas for juvenile fishes in Chwaka Bay, Zanzibar: gut content and stable isotope analyses

The relative importance of bay habitats, consisting of mangrove creeks and channel, seagrass beds, and mud and sand flats, as feeding grounds for a number of fish species was studied in Chwaka Bay, Zanzibar, Tanzania, using gut content analysis and stable isotope analysis of carbon and nitrogen. Gut content analysis revealed that within fish species almost the same food items were consumed regardless of the different habitats in which they were caught. Crustaceans (mainly copepods, crabs and shrimps) were the preferred food for most zoobenthivores and omnivores, while fishes and algae were the preferred food for piscivores and herbivores, respectively. The mean δ¹³C values of fishes and food items from the mangrove habitats were significantly depleted to those from the seagrass habitats by 6·9 and 9·7‰ for fishes and food items, respectively, and to those from the mud and sand flats by 3·5 and 5·8‰, respectively. Fishes and food items from the mud and sand flats were significantly depleted as compared to those of the seagrass habitats by 3·4 and 3·9‰, for fishes and food, respectively. Similar to other studies done in different geographical locations, the importance of mangrove and seagrass themselves as a primary source of carbon to higher trophic levels is limited. The different bay habitats were all used as feeding grounds by different fish species. Individuals of the species Gerres filamentosus , Gerres oyena , Lethrinus lentjan , Lutjanus fulviflamma , Pelates quadrilineatus and Siganus sutor appeared to show a connectivity with respect to feeding between different habitats by having δ¹³C values which were in-between those of food items from two neighbouring habitats. This connectivity could be a result of either daily tidal migrations or recent ontogenetic migration.     

New insights into the molecular phylogeny and taxonomy of mormyrids (Osteoglossiformes,Actinopterygii) in northern East Africa

Based on morphological data and analysis of mitochondrial cytochrome b gene and nuclear (S7 intron 1) DNA sequences, the phylogenetic relationships of all Pollimyrus species known from the Omo‐Turkana enclosed basin and Nile system below the Murchison Falls were solved. A mormyrid “Pollimyrus” petherici is distantly related to all other studied Pollimyrus species and clusters together with Cyphomyrus species forming with the later a monophyletic group. Moreover, the West African (but not the Congo River) populations of Cyphomyrus psittacus, the type species of the genus, seem to be conspecific to C. petherici. That is, the range of the genus Cyphomyrus is extended toward the Nile and Omo‐Turkana basins. This genus belongs to the large clade widely distributed in sub‐Saharian Africa and characterized by the presence of a chin appendage. Significance of this character for mormyrid phylogeny is discussed. Two distinct lineages of Pollimyrus occurring sympatrically in the White Nile tributaries and previously reported as the light and dark forms of Pollimyrus isidori together with five other congeneric species studied form a monophyletic group. The light form apparently represents P. isidori distributed in the Nile system downstream of the Murchison Falls and West Africa; the dark‐colored form (designated as Pollimyrus “D”) represents a distinct phylogenetic lineage inhabiting both the Omo‐Turkana and the White Nile basin. Morphological and ecological data suggest that this form may be conspecific to East African Pollimyrus nigricans or most probably represents a new species.     

Saldanha Bay,South Africa: recovery of Gracilaria verrucosa (Gracilariales,Rhodophyta)

Since World War II the greater Saldanha Bay lagoon system, South Africa, has been an important Gracilaria producer. Two agar factories, built in the 1960's, used Gracilaria from Saldanha Bay as their raw material. In the early 1970's the industry was destroyed as a result of dredging and marine construction operations to establish a harbor in the bay for loading ore. These environmental changes destroyed stocks and prevented the previously significant beachings of the seaweed from occurring. After a few years of no or very low commercial production, the resource slowly started to recover. The size of Gracilaria drifts increased over the following eight years to approximately one-third of the original output. This trend seems to continue. Although the stocks and resultant drifts are unlikely to recover fully to their original quantity, current production is already sufficient to ensure re-establishment of a seaweed industry in Saldanha Bay. This could have considerable socio-economic impact on the area.     

Phylogenetic relationships in Monanthes (Crassulaceae) based on morphological,chloroplast and nuclear DNA variation

Phylogenetic relationships of all 10 recognized taxa of the genus Monanthes which is endemic to the Canary Islands and Salvage Islands, were investigated using the four data sets: morphology, sequences of the chloroplast DNA trnL (UAA) — trnF (GAA) intergenic spacer, ITS2 sequences of the nuclear ribosomal region and Random Amplified Polymorphic DNAs (RAPDs). In contrast to the molecular data, the morphological data were internally inconsistent which probably resulted from parallel or convergent evolution of morphological characters. The molecular data sets indicated that the genus is not monophyletic due to inclusion of the annual M. icterica which is the putative sister taxon of Aichryson, that M. polyphylla is the sister taxon of the perennial species of the genus, that M. muralis from Hierro is of allotetraploid origin and that M. lowei, M. minima, M. brachycaulos, M. laxiflora, M. anagensis and M. muralis from La Palma are closely related. Combined ITS2 sequences, trnL — trnF sequences and morphological data indicated that the relationships among three types of perennial growth forms, i.e. tiny rosettes, small, branched shrubs and diffuse branches shrublets, are highly dependent on the outgroup used. After deletion of the most distant outgroup and a taxon of alleged hybrid origin (M. muralis) relationships among the growth forms of Monanthes still could not be consistently resolved.     

Seasonal variation in abundance of the Indian mackerel,Rastrelliger kanagurta Cuvier (Pisces: Scombridae) along the Zanzibar coast of East Africa

Purse-seine catches of the mackerel, Rastrelliger kanagurta Cuvier along the west coast of Zanzibar revealed seasonal patterns of abundance associated with monsoon winds. Low catches were obtained during the south-east monsoons while the north east monsoons were characterised by high catches. The largest sizes of mackerel were caught between June and August with a mixture of large and smaller ones between September and March. Mackerel in spawning condition were common between June and September with immature ones between September and January. The variations in mackerel abundance, size composition, and maturity of the fish are discussed in relation to seasonal changes, fish migrations, recruitment and food supply.     

Eucamaragnathus desenderi, a new ground beetle species from Africa (Coleoptera, Carabidae)

Eucamaragnathus desenderisp. n., a new ground beetle species of the tribe Hiletini, is described from eastern and southern Africa and dedicated to the recently deceased Belgian carabidologist Konjev Desender. The new taxon is known so far from localities in Zambia (Mukuku, southeast of Mansa) and in South Africa (Bothaville, south of Klerksdorp). The new species belongs to the Eucamaragnathus castelnaui group and is characterized by shape of pronotum, smooth or sparsely punctate pronotal transverse impression, characters of male genitalia and elytral striae continued to the apex. Illustrations of the habitus, the median lobe and its internal sac and several other morphological features are presented. An updated identification key to the African Eucamaragnathus species is given.     

Rothschild’s giraffe Giraffa camelopardalis rothschildi (Linnaeus, 1758) in East Africa: A review of population trends,taxonomy and conservation status

Giraffe populations have suffered a 40% decline in the past thirty years, making them a new priority for conservation and there are considerable uncertainty and disagreement over the taxonomic classification of giraffes. Consequently, there has never been a more critical time to fully understand the global population size and distribution of all giraffe subspecies. The Rothschild's giraffe Giraffa camelopardalis rothschildi (Linnaeus, 1758) is arguably one of the most imperilled giraffe subspecies. Once widespread across southern Sudan, Uganda and Kenya, the Rothschild's giraffe is now confined to a few, isolated and enclosed populations throughout Kenya and Uganda, with only one natural population remaining. Information about Rothschild's giraffe population size, distribution, and conservation history is patchy, and confined to recondite or inaccessible resources. Here, I present a review of taxonomy, distribution, conservation status and population size of the Rothschild's giraffe and present the most recent estimate of population sizes based on direct census data. Although the Latin name affixed to Rothschild's giraffe is subject to discussion, continued reference to this subspecies as G. c. rothschildi is strongly recommended.     

Evolution of the mitochondrial DNA control region in the mbuna (Cichlidae) species flock of lake Malawi, East Africa

Considerable controversy has surrounded the application of mitochondrial DNA data to reconstruction of evolutionary relationships among the endemic cichlids of Lake Malawi. Central to this debate has been the issue of whether lineage sorting is complete, and thus whether these data actually reflect species phylogeny, or simply gene genealogy. Review of all mtDNA control region sequences available for members of one monophyletic subset of this species flock, the Malawi rockfishes, or mbuna, strongly indicates that lineage sorting is incomplete: Character-based analyses of these sequences reconstruct gene, not species, interrelationships. Analysis of the pattern of nucleotide substitutions differentiating these mtDNA alleles suggests that pyrimidine residues undergo transition substitutions more often than do purines. Estimation of the magnitude of derived sequence differentiation in light of the reconstructed gene genealogy suggests that the mbuna may be of considerably more recent vintage than previous molecular characterizations have indicated. Received: 6 April 1996 / Accepted: 3 March 1997     

Doxomysis algoaensis, a new mysid species (Crustacea: Mysidacea) from Algoa Bay (South Africa)

Doxomysis algoaensis sp.nov. is described from Algoa Bay, South Africa where it is common in nearshore marine waters just beyond the breaker line. D. algoaensis sp.nov. is morphologically similar to D. australiensis, but can readily be distinguished by the shape and armature of the telson and the length of the exopod of the fourth male pleopod. The apical cleft is one fifth the telson length in the former species and one third the length in D. australiensis. The telson apex on each side of the cleft is also armed with five and four stout spines in the two species, respectively. In D. australiensis, the exopod of the fourth male pleopod is almost three times the length of the endopod; in D. algoaensis sp.nov., the exopod is only slightly longer than the endopod. Other distinctive features of D. algoaensis sp.nov. include the maxillary palp, which is only slightly broader than long and the greater number of spines on the endopod of the uropod.     

A new genus of Entiminae from North Africa,supported by a phylogenetic analysis (Coleoptera: Curculionidae: Entiminae)

The genus Holcophloeus gen. nov. is here proposed to include Trachyphloeus cruciatus Seidlitz, 1868, and two new species native to North Africa, based on a phylogenetic analysis and an evaluation of the diagnostic characters. The taxonomic position of Holcophloeus in relation to the tribes Trachyphloeini Lacordaire, 1863, and Holcorhinini Desbrochers, 1898, is discussed, and the new genus is attributed to the Holcorhinini. Holcophloeus laurae sp. nov. from south‐eastern Morocco and Holcophloeus weilli sp. nov. from northern Libya are described and illustrated and a key to the species of the new genus is given. The lectotype of Trachyphloeus cruciatus Seidlitz, 1868, is designated. The genus Massimiellus Borovec, 2009, is transferred from Trachyphloeini to Holcorhinini. © 2013 The Linnean Society of London     

Growth and phosphate uptake kinetics of the cyanobacterium,Cylindrospermopsis raciborskii (Cyanophyceae) in throughflow cultures

• 1 Cylindrospermopsis raciborskii occupies a rapidly expanding geographical area. Its invasive success challenges eutrophication control in many lakes. To understand better the load‐dependent behaviour of this nitrogen fixing cyanobacterium under in situ conditions, we studied P‐dependent growth of a C. raciborskii strain under continuous and pulsed P supply.
• 2 The Droop model reasonably described P‐dependent growth in the continuously supplied chemostats. Large P pulses, however, caused a delay in growth and cells subject to P pulses grew slower than their counterparts with the same P quota supplied continuously.
• 3 The kinetics of P uptake indicated that C. raciborskii is opportunistic with respect to P. Its high excess P storage capacity after a saturating P pulse (Q_ex=95 µg P [mg C]^‐1) and P‐specific uptake capacity (U_max = V_max/Q_P=150–1200) are indicative of storage adaptation. At the same time, the affinity of the P uptake system (U_max/K = 800–4000) is also high.
• 4 Rate of leakage exceeded that of the steady state net P uptake by one to two orders of magnitude. Growth affinity of C. raciborskii (µ_max/K_µ≈ 20) was relatively low, presumably due to the substantial leakage.
• 5 The dynamics of the particular water body determine which trait contributes most to competitive success of C. raciborskii. In deep lakes with vertical nutrient gradients, the cyanobacterium may rely primarily on its high P storage capacity, which is coupled to a lack of short‐term feedback inhibition and efficient buoyancy regulation. In lakes without such gradients, high P uptake affinity may be vitally important.

     

Survival, growth, health, and reproduction following nursery rearing compared with mother rearing in pigtailed monkeys (Macaca nemestrina)

Nursery-reared primates do not experience psychological "maternal bonding" or immunological benefits of breast milk, so they are expected to be inferior to mother-raised monkeys in growth, health, survival, reproduction, and maternal abilities. Studies of nursery-reared monkeys support aspects of this prediction for infants deprived of social contact or raised in pairs. We present colony record data on 1,187 mother and 506 nursery-raised monkeys, 2-10 yr of age, living in mixed groups. We found no group differences in survival, growth, clinical treatments for disease or bite wounds, or pregnancy outcome and neonatal deaths. Nursery males given breeding opportunities produced an average of 24 offspring. In addition to 24-hr personnel present on every day of the year, we believe that three of our procedures account for differences between our results and other reports. Our infants received 1) intensive human handling, 2) daily social interaction in a playroom, and 3) success and failure experience during learning and cognitive testing. We do not advocate rearing primates without mothers, but we conclude that these procedures are sufficient for producing physical health and adaptive juvenile and adult social skills in nursery-raised monkeys.     

Xenopus laevis larvae (Amphibia,Anura) as model suspension feeders

Larvae of the South African clawed frog, Xenopus laevis (Daudin), are efficient, obligate suspension feeders. We examine the relationship between the ambient particle concentration offered these larvae as food and their filtering, ingestion, and buccal pumping rates. We demonstrate that: (i) the larvae can sense and respond to a broad range of particle concentrations, down to 0.2 mg 1^–1 (dry weight); (ii) their metabolic needs theoretically can be met by particle concentrations as low as 5 mg 1^–1; and (iii) their patterns of regulation of filtering and ingestion fit predictions from certain models used to describe zooplankton feeding dynamics. Two such models are discussed: the modified Monod (Michaelis-Menten) model, with a lower threshold below which the tadpoles do not feed, and an energy optimization model. Both the models and the observed behavior of the tadpoles allow for stability of populations of food organisms. Tadpole feeding dynamics apparently are compatible with both the predictions and assumptions of these models, suggesting similar regulation of feeding by tadpoles and zooplankton. However, the size, morphology, and behavior of X. laevis larvae make their feeding regulation uniquely accessible to direct observation.Contribution No. 223, Center for Great Lakes Studies, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin.Contribution No. 223, Center for Great Lakes Studies, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin.