Chemical contaminants, pathogen exposure and general health status of live and beach-cast Washington sea otters (Enhydra lutris kenyoni)

Analyses of blood and liver samples from live captured sea otters and liver samples from beachcast sea otter carcasses off the remote Washington coast indicate relatively low exposure to contaminants, but suggest that even at the low levels measured, exposure may be indicated by biomarker response. Evidence of pathogen exposure is noteworthy - infectious disease presents a potential risk to Washington sea otters, particularly due to their small population size and limited distribution. During 2001 and 2002, 32 sea otters were captured, of which 28 were implanted with transmitters to track their movements and liver and blood samples were collected to evaluate contaminant and pathogen exposure. In addition, liver samples from fifteen beachcast animals that washed ashore between 1991 and 2002 were analyzed to provide historical information and a basis of reference for values obtained from live otters. The results indicate low levels of metals, butyltins, and organochlorine compounds in the blood samples, with many of the organochlorines not detected except polychlorinated biphenyls (PCBs), and a few aromatic hydrocarbons detected in the liver of the live captured animals. Aliphatic hydrocarbons were measurable in the liver from the live captured animals; however, some of these are likely from biogenic sources. A significant reduction of vitamin A storage in the liver was observed in relation to PCB, dibutyltin and octacosane concentration. A significant and strong positive correlation in vitamin A storage in the liver was observed for cadmium and several of the aliphatic hydrocarbons. Peripheral blood mononuclear cell (PBMC) cytochrome P450 induction was elevated in two of 16 animals and may be potentially related to aliphatic and aromatic hydrocarbon exposure. Mean concentration of total butyltin in the liver of the Washington beach-cast otters was more than 15 times lower than the mean concentration reported by Kannan et al. (1998) for Southern sea otters in California. Organochlorine compounds were evident in the liver of beach-cast animals, despite the lack of large human population centers and development along the Washington coast. Concentrations of PCBs and chlordanes (e.g., transchlordane, cis-chlordane, trans-nonachlor, cis-nonachlor and oxychlordane) in liver of Washington beach-cast sea otters were similar to those measured in Aleutian and California sea otters, excluding those from Monterey Bay, which were higher. Mean concentrations of 1,1,1,- trichloro-2,2-bis(p-chlorophyenyl)ethanes (DDTs) were lower, and mean concentrations of cyclohexanes (HCH, e.g., alpha BHC, beta BHC, delta BHC and gamma BHC) were slightly higher in Washington beach-cast otters versus those from California and the Aleutians. Epidemiologically, blood tests revealed that 80 percent of the otters tested positive for morbillivirus and 60 percent for Toxoplasma, the latter of which has been a significant cause of mortality in Southern sea otters in California. This is the first finding of positive morbillivirus titers in sea otters from the Northeast Pacific. Individual deaths may occur from these diseases, perhaps more so when animals are otherwise immuno-compromised or infected with multiple diseases, but a population-threatening die-off from these diseases singly is unlikely while population immunity remains high. The high frequency of detection of morbillivirus and Toxoplasma in the live otters corresponds well with the cause of death of stranded Washington sea otters reported herein, which has generally been attributable to infectious disease. Washington’s sea otter population continues to grow, with over 1100 animals currently inhabiting Washington waters; however, the rate of growth has slowed over recent years. The population has a limited distribution and has not yet reached its carrying capacity and as such, is still considered at high risk to catastrophic events. (PDF contains 189 pages

Light Influences Feeding and Growth of Echinoplutei.

Because planktonic invertebrate larvae may be food-limited, anything that increases feeding and digestive efficiency should increase the chances of larval survival to metamorphosis. As light directly enhances both feeding and digestion in some planktonic heterotrophic protists, we hypothesize that similar processes might occur in the larvae of marine invertebrates. We studied the direct effects of light on feeding and development in sea urchin larvae (Strongylocentrotus droebachiensis, S. franciscanus and sand dollar Dendraster excentricus). Larvae were placed in 12:12 h light:dark cycles or in complete darkness and ingestion rates were measured. We monitored larval morphology during the first 2 to 3 wk of development and tested for light-related differences. Short-term changes in light regime had no effect on feeding rates. However, larvae of all 3 species showed longer-term diel feeding patterns with ingestion rates generally higher during daylight hours. These patterns persisted in S. franciscanus larvae even when larvae were held in complete darkness for 3 d. Larvae of D. excentricus exposed to natural light cycles developed longer arms usually associated with food limitation; those held in darkness had significantly shorter arms. The developing juvenile structures (i.e., rudiments) of S. droebachiensis larvae exposed to light were significantly smaller than those of larvae held in continuous darkness, suggesting that light may have negative effects on larval growth and development. Measuring the effects of light on feeding and growth may clarify the behaviors of invertebrate larvae during their critically important planktonic period

Egg parasitoids of the genus Trichogramma (Hymenoptera, Trichogrammatidae) in olive groves of the Mediterranean region

A survey of egg parasitoids of the genus Trichogramma (Hymenoptera, Trichogrammatidae) was carried out in olive groves in Portugal, Greece, Egypt, and Tunisia during the years 2002–2004. Parasitoids were obtained either by exposing sentinel eggs (Sitotroga cerealella Olivier or Ephestia kuehniella Zeller) on olive trees or by collecting eggs of lepidopterous olive pests. Parasitized egg samples were reared separately in the laboratory for emergence of parasitoids. These were further reared in separate lines and processed by morphological and molecular biology techniques for species characterization. The recorded fauna of Trichogramma parasitoids in olive groves was species poor and consisted of species mainly known from the Mediterranean region. Trichogramma bourarachae Pintureau and Babault was found in Tunisia and Egypt, T. cordubensis Vargas and Cabello, and T. euproctidis Girault in Egypt, Trichogramma cacoeciae Marchal in Portugal, Greece, Egypt, Tunisia and Trichogramma nerudai Pintureau and Gerding in Portugal. Apart from that, Trichogramma oleae Voegele´ and Pointel was collected in Tunisia. This species is probably not indigenous, but has established after several releases of a French strain were made in recent years. For selected strains, the sequence of the internal transcribed spacer 2 (ITS-2) region of rDNA was determined and deposited in the GenBank database. Differences in important biological attributes were found among collected strains of T. bourarachae, suggesting the existence of biotypes. The results contribute to the limited knowledge on distribution and biodiversity of the genus Trichogramma in the Mediterranean region. They can be helpful for the preservation and use of indigenous Trichogramma species in biological control of lepidopterous pests in olive and other local crops

Pest categorisation of Apium virus Y

Following a request from the EU Commission, the EFSA Panel on Plant Health conducted a pest categorisation of Apium virus Y (ApVY) for the EU territory. The identity of the ApVY, a member of the genus Potyvirus (family Potyviridae), is well established and reliable detection methods are available. The pathogen is not included in EU Commission Implementing Regulation 2019/2072. ApVY, considered endemic in Australia, was reported also in New Zealand and USA. In the EU, the virus was identified in Germany and Slovenia. No information on adoption of official control measures is available. In natural conditions, ApVY infects plant species of the family Apiaceae (i.e. celery, coriander, dill, parsley, bishop’s weed) in which it generally induces leaf symptoms and/or stunting. In some hosts (i.e. parsley and poison hemlock), ApVY may be asymptomatic. The virus is transmitted in a non-persistent manner by the aphid Myzus persicae which is widespread in the EU. Although ApVY transmission through seeds has been experimentally excluded for some hosts (i.e. poison hemlock and celery), uncertainty exists for the other hosts because seed transmission is not uncommon for potyvirids. Plants for planting, including seeds for sowing, were identified as potential pathways for entry of ApVY into the EU. Cultivated and wild hosts of ApVY are distributed across the EU. Economic impact on the production of the cultivated hosts is expected if further entry and spread in the EU occur. Phytosanitary measures are available to prevent further entry and spread of the virus. Currently, ApVY does not fulfil the criterion of being absent or present with restricted distribution and under official control to be regarded as a potential Union quarantine, unless official control is implemented. This conclusion is associated with high uncertainty regarding the current virus distribution in the EU

Pest categorisation of carrot thin leaf virus

Following a request from the EU Commission, the EFSA Panel on Plant Health conducted a pest categorisation of carrot thin leaf virus (CTLV) for the EU territory. The identity of CTLV, a member of the genus Potyvirus (family Potyviridae), is well established and reliable detection methods are available. The pathogen is not included in the EU Commission Implementing Regulation 2019/2072. CTLV has been reported from the USA and Colombia. In the EU, the virus was reported in Germany and Slovenia and the NPPO of both countries confirmed these reports. No official national measures have been taken so far. In 2018, CTLV was reported from Greece on Torilis arvensis subsp. arvensis. Since then, no other reports exist. According to the NPPO, the virus did not establish in Greece. In natural conditions, CTLV infects plant species of the family Apiaceae (i.e., carrot, coriander, parsley and several wild weed species). The virus is transmitted in a non-persistent manner by the aphids Myzus persicae and Cavariella aegopodii, which are widely distributed in the EU. CTLV has been reported not to be transmitted by carrot seeds, while no information is available for the other hosts. Since transmission through seeds is not uncommon for potyvirids, it cannot be excluded that CTLV can be seed transmitted for some hosts. Plants for planting, including seeds for sowing, were identified as potential pathways for entry of CTLV into the EU. Cultivated and wild hosts of CTLV are distributed across the EU. Economic impact on the production of cultivated hosts is expected if further entry and spread in the EU occur. Phytosanitary measures are available to prevent further entry and spread of the virus on its cultivated hosts. Currently, CTLV does not fulfil the criterion of being absent or present with restricted distribution and under official control to be regarded as a potential Union quarantine pest, unless official control is implemented. This conclusion is associated with high uncertainty regarding the current virus distribution in the EU