Depression, anxiety and PTSD symptoms before and during the COVID-19 pandemic in the UK

BACKGROUND

The impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health is still being unravelled. It is important to identify which individuals are at greatest risk of worsening symptoms. This study aimed to examine changes in depression, anxiety and post-traumatic stress disorder (PTSD) symptoms using prospective and retrospective symptom change assessments, and to find and examine the effect of key risk factors.

METHOD

Online questionnaires were administered to 34 465 individuals (aged 16 years or above) in April/May 2020 in the UK, recruited from existing cohorts or via social media. Around one-third (n = 12 718) of included participants had prior diagnoses of depression or anxiety and had completed pre-pandemic mental health assessments (between September 2018 and February 2020), allowing prospective investigation of symptom change.

RESULTS

Prospective symptom analyses showed small decreases in depression (PHQ-9: -0.43 points) and anxiety [generalised anxiety disorder scale - 7 items (GAD)-7: -0.33 points] and increases in PTSD (PCL-6: 0.22 points). Conversely, retrospective symptom analyses demonstrated significant large increases (PHQ-9: 2.40; GAD-7 = 1.97), with 55% reported worsening mental health since the beginning of the pandemic on a global change rating. Across both prospective and retrospective measures of symptom change, worsening depression, anxiety and PTSD symptoms were associated with prior mental health diagnoses, female gender, young age and unemployed/student status.

CONCLUSIONS

We highlight the effect of prior mental health diagnoses on worsening mental health during the pandemic and confirm previously reported sociodemographic risk factors. Discrepancies between prospective and retrospective measures of changes in mental health may be related to recall bias-related underestimation of prior symptom severity.

The MPA Guide: A framework to achieve global goals for the ocean

[Figure: see text].

Perspectives on area-based conservation and its meaning for future biodiversity policy

During 2021, Parties to the Convention on Biological Diversity (CBD) are expected to meet in Kunming, China, to agree on a new global biodiversity framework aimed at halting and reversing biodiversity loss, encouraging the sustainable use of biodiversity, and ensuring the equitable sharing of its benefits. As the post-2020 global biodiversity framework evolves, parties to the convention are being exposed to a range of perspectives on the conservation and sustainable use of biodiversity, relating to the future framework as a whole or to aspects of it. Area-based conservation measures are one such aspect, and there are diverse perspectives on how new targets might be framed in relation to these measures. These perspectives represent different outlooks on the relationship between human and nonhuman life on Earth. However, in most cases there is a lack of clarity on how they would be implemented in practice, the implications this would have for biodiversity and human well-being, and how they would contribute to achieving the 2050 Vision for Biodiversity of "living in harmony with nature." We sought to clarify these issues by summarizing some of these perspectives in relation to the future of area-based biodiversity conservation. We identified these perspectives through a review of the literature and expert consultation workshops and compiled them into 4 main groups: Aichi+, ambitious area-based conservation perspectives, new conservation, and whole-earth conservation. We found that although the perspectives Aichi+ and whole earth are in some cases at odds with one another, they also have commonalities, and all perspectives have elements that can contribute to developing and implementing the post-2020 global biodiversity framework and achieving the longer term CBD 2050 Vision.

Author Correction: Area-based conservation in the twenty-first century

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Area-based conservation in the twenty-first century

Humanity will soon define a new era for nature-one that seeks to transform decades of underwhelming responses to the global biodiversity crisis. Area-based conservation efforts, which include both protected areas and other effective area-based conservation measures, are likely to extend and diversify. However, persistent shortfalls in ecological representation and management effectiveness diminish the potential role of area-based conservation in stemming biodiversity loss. Here we show how the expansion of protected areas by national governments since 2010 has had limited success in increasing the coverage across different elements of biodiversity (ecoregions, 12,056 threatened species, 'Key Biodiversity Areas' and wilderness areas) and ecosystem services (productive fisheries, and carbon services on land and sea). To be more successful after 2020, area-based conservation must contribute more effectively to meeting global biodiversity goals-ranging from preventing extinctions to retaining the most-intact ecosystems-and must better collaborate with the many Indigenous peoples, community groups and private initiatives that are central to the successful conservation of biodiversity. The long-term success of area-based conservation requires parties to the Convention on Biological Diversity to secure adequate financing, plan for climate change and make biodiversity conservation a far stronger part of land, water and sea management policies.

Integrating climate adaptation and biodiversity conservation in the global ocean

The impacts of climate change and the socioecological challenges they present are ubiquitous and increasingly severe. Practical efforts to operationalize climate-responsive design and management in the global network of marine protected areas (MPAs) are required to ensure long-term effectiveness for safeguarding marine biodiversity and ecosystem services. Here, we review progress in integrating climate change adaptation into MPA design and management and provide eight recommendations to expedite this process. Climate-smart management objectives should become the default for all protected areas, and made into an explicit international policy target. Furthermore, incentives to use more dynamic management tools would increase the climate change responsiveness of the MPA network as a whole. Given ongoing negotiations on international conservation targets, now is the ideal time to proactively reform management of the global seascape for the dynamic climate-biodiversity reality.

Dynamics in the global protected-area estate since 2004

Nations of the world have committed to a number of goals and targets to address global environmental challenges. Protected areas have for centuries been a key strategy in conservation and play a major role in addressing current challenges. The most important tool used to track progress on protected-area commitments is the World Database on Protected Areas (WDPA). Periodic assessments of the world's protected-area estate show steady growth over the last 2 decades. However, the current method, which uses the latest version of the WDPA, does not show the true dynamic nature of protected areas over time and does not provide information on sites removed from the WDPA. In reality, this method can only show growth or remain stable. We used GIS tools in an approach to assess protected-area change over time based on 12 temporally distinct versions of the WDPA that quantify area added and removed from the WDPA annually from 2004 to 2016. Both the narrative of continual growth of protected area and the counter-narrative of protected area removal were overly simplistic. The former because growth was almost entirely in the marine realm and the latter because some areas removed were reprotected in later years. On average 2.5 million km² was added to the WDPA annually and 1.1 million km² was removed. Reasons for the inclusion and removal of protected areas in the WDPA database were in part due to data-quality issues but also to on-the-ground changes. To meet the 17% protected-area component of Aichi Biodiversity Target 11 by 2020, which stood at 14.7% in 2016, either the rate of protected-area removal must decrease or the rate of protected-area designation and addition to the WDPA must increase.

Measuring the extent of overlaps in protected area designations

Over the past decades, a number of national policies and international conventions have been implemented to promote the expansion of the world’s protected area network, leading to a diversification of protected area strategies, types and designations. As a result, many areas are protected by more than one convention, legal instrument, or other effective means which may result in a lack of clarity around the governance and management regimes of particular locations. We assess the degree to which different designations overlap at global, regional and national levels to understand the extent of this phenomenon at different scales. We then compare the distribution and coverage of these multi-designated areas in the terrestrial and marine realms at the global level and among different regions, and we present the percentage of each county’s protected area extent that is under more than one designation. Our findings show that almost a quarter of the world’s protected area network is protected through more than one designation. In fact, we have documented up to eight overlapping designations. These overlaps in protected area designations occur in every region of the world, both in the terrestrial and marine realms, but are more common in the terrestrial realm and in some regions, notably Europe. In the terrestrial realm, the most common overlap is between one national and one international designation. In the marine realm, the most common overlap is between any two national designations. Multi-designations are therefore a widespread phenomenon but its implications are not well understood. This analysis identifies, for the first time, multi-designated areas across all designation types. This is a key step to understand how these areas are managed and governed to then move towards integrated and collaborative approaches that consider the different management and conservation objectives of each designation.

Eosinophilic myocarditis: characteristics, diagnostics and outcomes of a rare condition

Eosinophilic myocarditis is a rare and potentially fatal condition characterised by eosinophilic inflammatory infiltration of myocardium. We report seven consecutive cases of eosinophilic myocarditis at our centre and discuss the important characteristics, investigation and management of this disease.

A global map of saltmarshes

Background

Saltmarshes are extremely valuable but often overlooked ecosystems, contributing to livelihoods locally and globally through the associated ecosystem services they provide, including fish production, carbon storage and coastal protection. Despite their importance, knowledge of the current spatial distribution (occurrence and extent) of saltmarshes is incomplete. In light of increasing anthropogenic and environmental pressures on coastal ecosystems, global data on the occurrence and extent of saltmarshes are needed to draw attention to these critical ecosystems and to the benefits they generate for people. Such data can support resource management, strengthen decision-making and facilitate tracking of progress towards global conservation targets set by multilateral environmental agreements, such as the Aichi Biodiversity Targets of the United Nations' (UN's) Strategic Plan for Biodiversity 2011-2020, the Sustainable Development Goals of the UN's 2030 Agenda for Sustainable Development and the Ramsar Convention.

New information

Here, we present the most complete dataset on saltmarsh occurrence and extent at the global scale. This dataset collates 350,985 individual occurrences of saltmarshes and presents the first global estimate of their known extent.

The dataset captures locational and contextual data for saltmarsh in 99 countries worldwide. A total of 5,495,089 hectares of mapped saltmarsh across 43 countries and territories are represented in a Geographic Information Systems polygon shapefile. This estimate is at the relatively low end of previous estimates (2.2-40 Mha), however, we took the conservative approach in the mapping exercise and there are notable areas in Canada, Northern Russia, South America and Africa where saltmarshes are known to occur that require additional spatial data. Nevertheless, the most extensive saltmarsh worldwide are found outside the tropics, notably including the low-lying, ice-free coasts, bays and estuaries of the North Atlantic which are well represented in our global polygon dataset. Therefore, despite the gaps, we believe that, while incomplete, our global polygon data cover many of the important areas in Europe, the USA and Australia.

Assessing the Cost of Global Biodiversity and Conservation Knowledge

Knowledge products comprise assessments of authoritative information supported by standards, governance, quality control, data, tools, and capacity building mechanisms. Considerable resources are dedicated to developing and maintaining knowledge products for biodiversity conservation, and they are widely used to inform policy and advise decision makers and practitioners. However, the financial cost of delivering this information is largely undocumented. We evaluated the costs and funding sources for developing and maintaining four global biodiversity and conservation knowledge products: The IUCN Red List of Threatened Species, the IUCN Red List of Ecosystems, Protected Planet, and the World Database of Key Biodiversity Areas. These are secondary data sets, built on primary data collected by extensive networks of expert contributors worldwide. We estimate that US$160 million (range: US$116–204 million), plus 293 person-years of volunteer time (range: 278–308 person-years) valued at US$ 14 million (range US$12–16 million), were invested in these four knowledge products between 1979 and 2013. More than half of this financing was provided through philanthropy, and nearly three-quarters was spent on personnel costs. The estimated annual cost of maintaining data and platforms for three of these knowledge products (excluding the IUCN Red List of Ecosystems for which annual costs were not possible to estimate for 2013) is US$6.5 million in total (range: US$6.2–6.7 million). We estimated that an additional US$114 million will be needed to reach pre-defined baselines of data coverage for all the four knowledge products, and that once achieved, annual maintenance costs will be approximately US$12 million. These costs are much lower than those to maintain many other, similarly important, global knowledge products. Ensuring that biodiversity and conservation knowledge products are sufficiently up to date, comprehensive and accurate is fundamental to inform decision-making for biodiversity conservation and sustainable development. Thus, the development and implementation of plans for sustainable long-term financing for them is critical.

Measuring impact of protected area management interventions: current and future use of the Global Database of Protected Area Management Effectiveness

Protected areas (PAs) are at the forefront of conservation efforts, and yet despite considerable progress towards the global target of having 17% of the world's land area within protected areas by 2020, biodiversity continues to decline. The discrepancy between increasing PA coverage and negative biodiversity trends has resulted in renewed efforts to enhance PA effectiveness. The global conservation community has conducted thousands of assessments of protected area management effectiveness (PAME), and interest in the use of these data to help measure the conservation impact of PA management interventions is high. Here, we summarize the status of PAME assessment, review the published evidence for a link between PAME assessment results and the conservation impacts of PAs, and discuss the limitations and future use of PAME data in measuring the impact of PA management interventions on conservation outcomes. We conclude that PAME data, while designed as a tool for local adaptive management, may also help to provide insights into the impact of PA management interventions from the local-to-global scale. However, the subjective and ordinal characteristics of the data present significant limitations for their application in rigorous scientific impact evaluations, a problem that should be recognized and mitigated where possible.

Analysing biodiversity and conservation knowledge products to support regional environmental assessments

Two processes for regional environmental assessment are currently underway: the Global Environment Outlook (GEO) and Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES). Both face constraints of data, time, capacity, and resources. To support these assessments, we disaggregate three global knowledge products according to their regions and subregions. These products are: The IUCN Red List of Threatened Species, Key Biodiversity Areas (specifically Important Bird &Biodiversity Areas [IBAs], and Alliance for Zero Extinction [AZE] sites), and Protected Planet. We present fourteen Data citations: numbers of species occurring and percentages threatened; numbers of endemics and percentages threatened; downscaled Red List Indices for mammals, birds, and amphibians; numbers, mean sizes, and percentage coverages of IBAs and AZE sites; percentage coverage of land and sea by protected areas; and trends in percentages of IBAs and AZE sites wholly covered by protected areas. These data will inform the regional/subregional assessment chapters on the status of biodiversity, drivers of its decline, and institutional responses, and greatly facilitate comparability and consistency between the different regional/subregional assessments.

Malaria in a captively-produced F1 gyrfalcon and in two F. peregrine falcons

One Falco rusticolus and two of 24 Falco peregrinus were positive for Plasmodium relictum. Sixteen percent of the erythrocytes (RBC) of the gyrfalcon were parasitized. Following treatment with chloroquine the parasite burden was dramatically reduced (to less than 0.01%). Infection in peregrine falcons was low (0.01-0.4% RBCs were parasitized). This is the second report of Plasmodium in the gyrfalcon and the first report in the peregrine falcon.

The plant communities and environmental gradients of Pitcairn Island: the significance of invasive species and the need for conservation management

Quantitative surveys of the vegetation of south-east Polynesian Islands are rarely undertaken owing to time and logistical restrictions; however they are fundamental in determining the conservation status of fragile island ecosystems. The aim of the research was to document quantitatively the vegetation of Pitcairn Island by investigating whether clearly definable plant communities existed on the island, and the underlying environmental gradients influencing these communities. Initially, 10 x 10 m quadrats were taken from all areas of the island, with environmental parameters recorded for each quadrat. The vegetation was then mapped from high altitude vantage points. Two-way indicator species analysis was used to identify distinct plant communities, and canonical correspondence analysis was used to determine the underlying environmental gradients. The vegetation consists of 14 plant communities: four coastal, six forest, two fernland and two scrub communities. Large areas are covered by non-native scrub vegetation, and by monospecific Syzygium jambos (rose-apple) plantations. Less than 30 % of the island is covered by native forest, and these areas are limited to remote valleys. Fernlands also cover large areas, including both eroding areas and ridge tops. Coastal vegetation comprises rock and cliff communities with limited strand vegetation. The major environmental gradient affecting the composition of the plant communities is altitude, but anthropogenic influences also have a large effect, owing to forest clearance and introduced species. The light environment is affected by the canopy species, and determines what ground flora can develop. Identification of distinct plant communities has allowed for a system of nature reserves to be suggested, which conserve all of these plant communities and a significant proportion of the threatened plant species.

Invasive entamoebae in pronghorn (Antilocapra americana) from Wyoming

Trophozoites and cysts of an amoeba resembling Entamoeba bovis were recovered from soft stools of captive pronghorn fawns (Antilocapra americana). Chronic or intermittent diarrhea was observed in most individuals in two groups of hand-raised 1- to 8-mo-old pronghorns. Ileocecal lymph nodes were mildly to moderately enlarged. Microscopic lesions were characterized by lymphoid hyperplasia, focal necrosis and pyogranulomatous inflammation in lymph nodes and focal necrosis and diffuse nonsuppurative enteritis in ileum and cecum. In 12 of 17 fawns, trophic stages of amoebae were observed in the submucosa of the cecum and/or the cortex of the ileocecal lymph node. This is the first report of E. bovis-like organisms invading and causing pathological changes in the tissues of their host.

Trypanosoma cervi from Alaskan reindeer, Rangifer tarandus

Twenty-nine (64.4%) or 45 reindeer, Rangifer tarandus, examined over a two-year period were infected with trypanosomes. Trypomastigotes and dividing epimastigotes were found in the blood of fawns, cows, and bulls. Morphometric analysis of bloodstream trypomastigotes from reindeer and comparison of these parasites with similar stages of trypanosomes from elk, mule deer, and white-tailed deer from the continuous United States proved them conspecific; the trypanosomes from these members of the Cervidae are identified as Trypanosoma cervi Kingston & Morton, 1975. This is the first report of trypanosomes from reindeer. No pathogenic effects are known to be caused by these parasites.

Further studies on trypanosomes in game animals in Wyoming II

Further studies on moose revealed trypanosomes in two captive moose (Alces alces shirasi) and in 4 of 7 free-ranging moose in Wyoming by blood culture. Two free-ranging moose from Utah were negative. One of two additional captive moose calves was positive for trypanosomes. Trypanosomes also were detected in blood cultures of 8 of 39 American Bison (Bison bison) being brought into Wyoming from Nebraska. Nineteen additional bison were negative for trypanosomes by blood cultures. Identification of species was not possible due to the failure to obtain bloodstream trypomastigotes from this host. Trypanosomes were recovered from 8 of 57 pronghorn antelope (Antilocapra americana). This is the first report of Trypanosoma sp. from bison and from pronghorn; the trypanosome from moose was identified as Trypanosoma cervi from bloodstream trypomastigotes. In 1978, natural transplacental transmission of trypanosomes was found to occur in 1 of 15 mule deer (Odocoileus hemionus) fetuses, examined near term by blood culture. No trypanosomes were found in 18 male deer fetuses examined in 1979. Of 100 free-ranging elk from western Wyoming examined by blood culture in 1979, 71 were infected. These data are compared with data from 1973-74.

Trypanosoma theileri Laveran, 1902, in Wyoming cattle

Trypanosoma theileri Laveran, 1902, a cosmopolitan blood parasite of cattle, was found in 86 of 377 Wyoming cattle. Acute infection was experimentally produced in 22 cattle, with blood stream trypanosomes reaching peaks (up to 8,00/ml) in the first 2 weeks of infection. Infection subsided after 3 to 4 weeks. In studies of animals with chronic infection, the parasites reappeared in the blood 4 to 6 months after initial exposure and again at 8 months. Morphologically, three trypomastigote forms were seen: short-thin forms, long-thin forms, and long-broad forms. It is considered that the first two types derived from the last. Comparisons of bloodstream trypomastigotes were made with chicken embryo culture forms, and it was concluded that identification and description of trypanosomes from cattle can be made only by examination of bloodstream stages.

Continuous cultivation of Trypanosoma theileri at 37 C in bovine cell culture

Trypanosoma theileri was cultivated at 37 C in bovine bone marrow cell culture through 50 consecutive subcultures. Medium 199, supplemented with Bacto-peptone, vitamin B12, and fetal bovine serum, was utilized both for primary and continuous cultivation. The number of trypanosomes produced in culture averaged 8 x 10(6) (1-26 x 10(6)) trypanosomes/ml. In each subculture the organisms divided as epimastigotes and transformed into trypomastigotes; a round from was observed during the stationary and declining phase of growth. Gradual changes such as increased generation time, size reduction, and decreased trypomastigote production were observed as subculturing progressed. Cultured trypanosomes were infective for the bovine through the 48th serial transfer and could be cultivated at 26 degrees C.

Two species of Entamoeba from white-tailed deer, Odocoileus virginianus, from Georgia

Large numbers of 2 species of Entamoeba, Entamoeba coli and Entamoeba bovis, were recovered from captive white-tailed deer from Georgia. The trophozoite of the first ameba was a large form with a well-defined vesicular nucleus bearing a prominent eccentric endosome, abundant peripheral chromatin, and numerous periendosomal granules. Cytoplasmic vacuoles containing bacteria and other substances were common. Mature cysts were octonucleate. Glycogen vacuoles and irregularly shaped chromatoids were frequently present. This ameba was identified as Entamoeba coli. The trophozoite of the second ameba was small, with a typical Entamoeba nucleus. Cysts were uninucleate, containing numerous chromatoids resembling bars, splinters of wood, and irregular masses. There was occasionally a glycogen vacuole. This ameba was identified as Entamoeba bovis.

Trypanosoma cervi Kingston and Morton, 1975 from mule deer, Odocoileus hemionus, in Wyoming

Mensural values of blood stream stages and cross-transmission studies defined the trypanosome species from mule deer, Odocoileus hemionus, as con-specific with Trypanosoma cervi, the trypanosome found in elk from the same locality. Trypanosomes were found in eight mule deer sampled in the spring and eight sampled in the winter in southeastern Wyoming.

Further studies on trypanosomers in game animals in Wyoming

Blood samples were collected from captive and free-ranging elk (Cervus canadensis), mule deer (Odocoileus hemionus), white-tailed deer, (Odocoileus virginianus), black-tailed deer (Odocoileus hemionus columbianus), pronghorn (Antilocapra americana), moose (Alces alces), and bighorn sheep (Ovis canadensis) for cultural evidence of Trypanosoma sp. infection. Eleven of 188 (12%) hunter-killed elk, 22 of 37 (59%) free-ranging elk, and 79 of 119 (66%) captive elk were culture positive in 1973-74. Parasitemia in adult captive elk showed seasonal variation. Other captive or live-trapped animals found positive included 16 mule deer, two white-tailed deer, and one black-tailed deer. No pronghorn, moose, or bighorn sheep were positive. A 0.25 ml inoculum of elk blood was sufficient to give positive culture results. Small sample size may have contributed to negative results from elk trapped in March 1973.

Trypanosomes from mule deer, Odocoileus hemionus in Wyoming

Examination of mule deer, Odocoileus hemionus, from Wyoming in Spring, 1974 (8) and in Winter of 1974-75 (8) revealed trypanosomes in all 16 deer. Spring samples showed dividing epimastigotes as well as normal bloodstream forms. Winter samples showed only normal blood stream forms. These differences are considered to be seasonally related.

Babesia moshkovskii (Schurenkova, 1938) Laird and Lari, 1957; from the prairie falcon, Falco mexicanus, in Wyoming; with comments on other parasites found in this host

Babesia moshkovskiiwas found in the blood of 6 of 30 downy (D) Prairie Falcons and in none of 5 adults (A) from Wyoming. Intestinal parasites included Neodiplostomum (C) spathula (A,3), Cladotaenia globifera, (A,1), Physaloptera sp., (A,1), and Serratospiculum amaculatum, (a,4). ornithodorus concanensis, (D,3), Thrassis francisi, (D,1), Opisocrostis sp., (D.1), Degeeriella rufa, (D,2), Simulium (E.) canonicola (D,2), and an unidentified hippoboscid fly, (D,2) were external parasites. It is considered that the soft tick, O. concanensis, is the most likely vector of the hematozoon. The morphological forms of B.moshkovskii are described and discussed. This is the first report of an avian babesoid on this continent.

Trypanosoma cervi sp. n. from elk (Cervus canadensis) in Wyoming

Trypanosoma cervi sp. n. is described from 22 trypomastigote syntypes from the blood of elk, Cervus canadensis, in North America (type locality: Wyoming). The blood trypomatigotes of T. cervi are compared with various culture forms: epimastigotes in 22 to 25 C NNN cultures; trypomastigotes in 37 C NNN cultures; and trypomastigotes from CAM chick embryo (10-day) cultures. Trypanosoma cervi is differentiated on morphological grounds from the cosmopolitan bovine species, T. theileri, and from T. ingens and T. mazamarum. Transmission of T. cervi to cattle was attempted using infected elk blood. No trypanosomal stages were recovered when recipients were examined by blood culture. The findings support the morphological data that T. cervi is distinct from T. theileri.

On the morphology and life cycle of the trematode Tanaisia zarudnyi (Skrjabin, 1924) Byrd and Denton, 1950, from the ruffed grouse, Bonasa umbellus L

Tanaisia zarudnyi occurs in the ureters and kidney tubules of ruffed grouse from Ontario and Michigan. The dark brown, operculate eggs are fully developed when oviposited. They remain viable for long periods of time at 2 to −15 °C and can withstand a temperature of −49 °C for 1 to 2 days. They hatch only when ingested by some mollusc. Development occurs in the digestive gland of the terrestrial snails Anguispira alternata and Succinea ovalis. Daughter sporocysts complete development in 6 weeks, by which time they contain undeveloped cercarial bodies. Within the next 2 weeks, most of the distomate. brevicercous cercariae are fully developed. The cercariae encyst within the daughter sporocyst, utilizing the contents of subcuticular glands to form the cyst. Encysted metacercariae are killed in the gizzard when fed to chickens, but excyst when inoculated directly into the duodenum. Excystation apparently results from secretions of the anterior glands of the stimulated metacercaria rather than from digestion of the cyst wall by the host. A 6-week-old ruffed grouse became infected when fed metacercariae, but 9 older ruffed grouse, 17 chickens, 4 white-throated sparrows, and 6 pheasants, fed similarly, were not infected. Apparently there is both host and age resistance to infection with this parasite.

On the life cycle of Brachylecithum orfi Kingston and Freeman, 1959 (Trematoda: Dicrocoeliidae), from the liver of the ruffed grouse, Bonasa umbellus L. infections in the vertebrate and molluscan hosts

The distribution and life cycle of a dicrocoeliid trematode, Brachylecithum orfi Kingston and Freeman, 1959, from the biliary ducts of the ruffed grouse, Bonasa umbellus, in Ontario and Michigan, have been studied in the definitive host and the intermediate molluscan hosts. Oval, dark brown, operculate eggs contain fully developed miracidia at oviposition. The eggs are coated with a lipid which prevents uptake of water and hatching until they are eaten by a mollusc; they will survive for more than 3 years at 2 °C and will tolerate exposure to −49 °C. The eggs hatch and larval stages develop in Zonitoides arboreus, Z. nitidus, Cionella lubrica, Deroceras laeve, and D. reticulatum, but not in 13 other species of terrestrial molluscs. Small, rounded, daughter sporocysts develop within the saclike mother sporocysts during the first 30 days after ingestion of eggs by suitable molluscs. Daughter sporocyst and cercarial development is completed 89–278 days after infection, depending on the species of mollusc and the temperature. The cercariae escape from the sporocyst endosac through a birth canal into the sinusoidal spaces of the mollusc. They migrate to the lung and out onto the dorsum of the mollusc via the respiratory pore, where they aggregate in numbers in slimeballs that are deposited on the substratum. Cercarial production continues for more than 100 days after onset. The longicercous, mesostomate xiphidiocercariae have a flame cell formula of 2((2 + 2 + 2) + (2 + 2 + 2)); they are provided with 6 preacetabular and 12 postacetabular glands, both groups of which open through pores lateral to the shank of the cercarial stylet. Cercariae in slime masses survive for 48 hours. When exposed to larval Colorado potato beetles, larval willow chrsyomelids, and mound-building ants, the cercariae penetrated the gut wall and encysted in the haemocoel, but died shortly afterwards.