The Transmission of Haemoproteus sp. of English Wood-pigeons by Ornithomyia avicularia

SYNOPSIS. Haemoproteus sp. (probably a subspecies of H., columbae Kruse, 1890) of Columba p. palumbus L. in England produces sporozoites in the salivary glands of Ornithomyia avicularia L. and has been transmitted by the bite of this insect. The parasite has also been isolated from naturallyinfected O. avicularia. Observations on experimentally-infected birds have shown that the macrogametocytes reach their full size in six days, and the microgametocytes in five. The taxonomy of the genus is briefly discussed.     

The Transport of Sugars in Developing Fruits of Satsuma Mandarin

Transport of sugars to the juice sacs of developing satsumamandarin (Citrus unshui Marc) has been studied in attached fruitsand in isolated fruit pieces. ¹⁴CO₂ fed to the leaves resultedin [¹⁴C]sugar accumulation in the juice sacs, mainly as [¹⁴C]sucrose.Uptake of sucrose and glucose by the excised fruit pieces proceededlinearly with time. Sucrose uptake was linearly related to sucroseconcentration over the range 25–300 mM, with no indicationof saturation. This uptake was insensitive to pH (5, 7 or 9),Ca²⁺(3 mM), PCMBS (2.5 mM), DNP (1 mM) or vanadate (0.1 mM)but was slightly reduced by erythrosin (21 % by 0–1 mM;27 % by 1 mM). No competitive effect of glucose (up to 100 mM)was detectable on sucrose uptake from 100 mM solution. Mostof the [¹⁴C]sucrose uptake observed was reversible, althoughconsiderable hydrolysis and metabolic conversion were evidenced.A vanadate-sensitive ATPase was demonstrated by EM localizationon the plasma membrane of the juice sac cells. These resultsare interpreted in relation to the accumulation of assimilatesby the developing fruit. Transport: sugar, satsuma mandarin, juice sacs     

Past and present distribution, densities and movements of blue whales Balaenoptera musculus in the Southern Hemisphere and northern Indian Ocean

• 1 Blue whale locations in the Southern Hemisphere and northern Indian Ocean were obtained from catches (303 239), sightings (4383 records of ≥8058 whales), strandings (103), Discovery marks (2191) and recoveries (95), and acoustic recordings.
• 2 Sighting surveys included 7 480 450 km of effort plus 14 676 days with unmeasured effort. Groups usually consisted of solitary whales (65.2%) or pairs (24.6%); larger feeding aggregations of unassociated individuals were only rarely observed. Sighting rates (groups per 1000 km from many platform types) varied by four orders of magnitude and were lowest in the waters of Brazil, South Africa, the eastern tropical Pacific, Antarctica and South Georgia; higher in the Subantarctic and Peru; and highest around Indonesia, Sri Lanka, Chile, southern Australia and south of Madagascar.
• 3 Blue whales avoid the oligotrophic central gyres of the Indian, Pacific and Atlantic Oceans, but are more common where phytoplankton densities are high, and where there are dynamic oceanographic processes like upwelling and frontal meandering.
• 4 Compared with historical catches, the Antarctic (‘true’) subspecies is exceedingly rare and usually concentrated closer to the summer pack ice. In summer they are found throughout the Antarctic; in winter they migrate to southern Africa (although recent sightings there are rare) and to other northerly locations (based on acoustics), although some overwinter in the Antarctic.
• 5 Pygmy blue whales are found around the Indian Ocean and from southern Australia to New Zealand. At least four groupings are evident: northern Indian Ocean, from Madagascar to the Subantarctic, Indonesia to western and southern Australia, and from New Zealand northwards to the equator. Sighting rates are typically much higher than for Antarctic blue whales.
• 6 South‐east Pacific blue whales have a discrete distribution and high sighting rates compared with the Antarctic. Further work is needed to clarify their subspecific status given their distinctive genetics, acoustics and length frequencies.
• 7 Antarctic blue whales numbered 1700 (95% Bayesian interval 860–2900) in 1996 (less than 1% of original levels), but are increasing at 7.3% per annum (95% Bayesian interval 1.4–11.6%). The status of other populations in the Southern Hemisphere and northern Indian Ocean is unknown because few abundance estimates are available, but higher recent sighting rates suggest that they are less depleted than Antarctic blue whales.