High bycatch rates of manta and devil rays in the “small-scale” artisanal fisheries of Sri Lanka

Background Expanding fisheries in developing nations like Sri Lanka have a significant impact on threatened marine species such as elasmobranchs. Manta and devil (mobulid) rays have some of the most conservative life history strategies of any elasmobranch, and even low to moderate levels of bycatch from gillnet fisheries may lead to significant population declines. A lack of information on life history, demographics, population trends, and fisheries impacts hinders effective management measures for these species. Method We report on mobulid fishery landings over nine years between 2011 and 2020 across 38 landing sites in Sri Lanka. We collected data on catch numbers, body sizes, sex, and maturity status for five mobulid species. We used a Bayesian state-space model to estimate monthly country-wide catch rates and total annual landings of mobulid rays. We used catch curve analyses to estimate total mortality for Mobula mobular, and evaluated trends in recorded body sizes across the study period for M. mobular, M. birostris, M. tarapacana and M. thurstoni. Results We find that catch rates have declined an order of magnitude for all species across the study period, and that total annual captures of mobulid rays by the Sri Lankan artisanal fishing fleet exceed the estimated annual captures of mobulids in all global, industrial purse seine fisheries combined. Catch curve analyses suggest that M. mobular is being fished at rates far above the species’ intrinsic population growth rate, and the average sizes of all mobulids in the fishery except for M. birostris are declining. Collectively, these findings suggest overfishing of mobulid ray populations in the northern Indian Ocean by Sri Lankan artisanal fisheries. We recommend strengthening the management of these species through improved implementation of CITES, CMS, and regional fisheries management actions. In addition, we report on the demographic characteristics of mobulids landed in Sri Lanka and provide the first record of M. eregoodoo in the country.

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THE EFFECT OF FERTILIZER SUBSIDY ON PADDY PRODUCTION OF SMALL SCALE FARMERS: SPECIAL REFERENCE IN POLONNARUWA DISTRICTIN SRI LANKA

Review of Behavioral Aspect in Organizations and Society ◽

10.32770/rbaos.vol133-44 ◽

2019 ◽

Vol 1 (1) ◽

pp. 33-44

Author(s):

M B Ranathilaka ◽

I.A.J Imbulana Arachchi

Keyword(s):

Sri Lanka ◽

Education Level ◽

Living Condition ◽

Alternative Methods ◽

Small Scale ◽

Sri Lankan ◽

Paddy Farmers ◽

Small Scale Farmers ◽

Paddy Cultivation ◽

Paddy Yield

Paddy cultivation is major part in rural agriculture sector in Sri Lanka. Majority of rural sector paddy farmers are small-scale producers. According to available data paddy production sector provides livelihood opportunities for large numbers of rural population, provide rice requirement of the nation, provide inputs to other industrial sector etc.To enhance small-scale farmers living condition as well as paddy production, Sri Lankan government promotes paddy farmers to use more fertilizer for their paddy cultivation activities. Therefore, Sri Lankan government provides subsidized fertilizer to enhance both paddy production and paddy yield per acre. Last few decades paddy production and paddy yield per acre data show continues increasing trend. At the same time government expenditure on fertilizer also becomes heavy burden to national budget. There are arguments for and against to fertilizer subsidy program and its practice. This study attempts to study the effect of fertilizer subsidy on paddy production and living condition of small-scale farmers in Polonnaruwa district in Sri Lanka. The data are used to estimate an econometric model to find the relationship between paddy productivity, fertilizer subsidy, agricultural infrastructure facilities and farmers education level. The data were collected from Bubula and Raja-elagama villages in Higurakgoda divisional secretariat in Polonnaruwa district. Structured questioner was used to collect the data from 150 farmers. The results show that there is significant relationship between paddy production and dependent variables named fertilizer subsidy, agricultural infrastructure facilities and farmers education level. Especially fertilizer subsidy and paddy productivity is significant at 5 per cent level and R2 was 0.68. This result shows that government main objective of fertilizer subsidy that improves paddy productivity has been fulfilled. At the same time, household income from paddy has also increased and it has affected their livelihoods. But poor agricultural infrastructural facilities have mitigated farmers’ income. Research results and some empirical evidence have concluded that it is important to find alternative methods to select suitable and needy farmers who are eligible to get fertilizer subsidy because conducting methods of distributing have made many kinds of effects on the efficiency of resource utilization, equity of income distribution as well as government budget. Agricultural infrastructure facilities are very important for making fertilizer subsidy programs more meaningful and to have a significant effect on enhancing paddy farmers’ living conditions.

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Causes of psychopathology

Textbook of Evolutionary Psychiatry and Psychosomatic Medicine ◽

10.1093/med:psych/9780198717942.003.0004 ◽

2015 ◽

pp. 94-112 ◽

Cited By ~ 1

Author(s):

Martin Brüne

Keyword(s):

Life History ◽

Human Life ◽

Well Being ◽

Life History Strategies ◽

Small Scale ◽

Immunological Diseases ◽

Proximate Causes ◽

Suboptimal Design ◽

Epigenetic Modulation ◽

The Impact

The causes of psychiatric and psychosomatic conditions can be categorized into two groups: proximate and ultimate (evolutionary) causes. Proximate causes comprise genetic factors, epigenetic modulation, childhood trauma and other life events, and senescence. Ultimate or evolutionary causes concern mismatch between adaptation and current environment, suboptimal design, and design compromises. Examples of evolutionary causes of dysfunction include cognitive and emotional adaptations to small-scale societies (mismatch), anxiety (suboptimal design), premature birth (design compromise), and other features associated with human life history. Furthermore, many ‘diseases of civilization’ fall under the category of mismatch, as well as immunological diseases that may arise from a lack of exposure to pathogens early in life. Prevention of psychopathology, though desirable, may not always be possible due to the fact that evolution does not select for emotional well-being. However, reducing the impact of early adversity and helping people develop alternative life-history strategies may be an attainable goal.

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Differing Life-History Strategies of Two Mycoheterotrophic Orchid Species Associated with Leaf Litter- and Wood-Decaying Fungi

Diversity ◽

10.3390/d13040161 ◽

2021 ◽

Vol 13 (4) ◽

pp. 161

Author(s):

Yuki Ogura-Tsujita ◽

Kenshi Tetsuka ◽

Shuichiro Tagane ◽

Miho Kubota ◽

Shuichiro Anan ◽

...

Keyword(s):

Life History ◽

Leaf Litter ◽

Mycorrhizal Fungi ◽

Life History Strategy ◽

Life History Strategies ◽

Small Scale ◽

Nutrient Depletion ◽

Saprotrophic Fungi ◽

Orchid Species ◽

Mycoheterotrophic Plants

Mycoheterotrophic orchids depend completely on mycorrhizal fungi for their supply of carbon. The life-history traits of mycoheterotrophic plants (MHPs) can differ according to the characteristics of the associated mycorrhizal fungi. We compared the life-history strategies of two mycoheterotrophic orchids associated with wood- and leaf litter-decaying fungi over a maximum of six years of field monitoring. Seventy percent of the aboveground stems of Erythrorchis altissima, associated with wood-decaying fungi, disappeared from the host wood within two years after tagging, likely due to nutrient depletion. In contrast, Gastrodia confusa, associated with leaf litter-decaying fungi, occurred continuously (18 to 108 fruiting stalks) every year within a small-scale plot (12 × 45 m) for six years through seed and clonal propagation. Our results support the idea that mycoheterotrophic orchids associated with wood-decaying fungi disappear from their habitats due to nutrient depletion after their host wood has mostly decayed, while mycoheterotrophic orchids associated with leaf litter-decaying fungi can survive in small-scale habitats where substantial leaf fall regularly occurs to sustain the associated fungi. Our study provides basic information about a unique life-history strategy in MHPs associated with saprotrophic fungi and an understanding of the variation in life-history strategies among MHPs.

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Life-History Strategies of Nile Tilapia, Oreochromis niloticus (Linnaeus, 1758) (Teleostei, Cichlidae), in Irrigation Reservoirs of Sri Lanka

Asian Fisheries Science ◽

10.33997/j.afs.2020.33.3.003 ◽

2020 ◽

Vol 33 (3) ◽

Author(s):

K.V. SANDUN N. BANDARA

Keyword(s):

Life History ◽

Sri Lanka ◽

Oreochromis Niloticus ◽

Nile Tilapia ◽

Life History Strategies ◽

Nile Tilapia Oreochromis Niloticus

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Within-host competition drives energy allocation trade-offs in an insect parasitoid

PeerJ ◽

10.7717/peerj.8810 ◽

2020 ◽

Vol 8 ◽

pp. e8810

Author(s):

J. Keaton Wilson ◽

Laura Ruiz ◽

Goggy Davidowitz

Keyword(s):

Life History ◽

Body Size ◽

Life History Theory ◽

Large Body ◽

Ecological Impacts ◽

Life History Strategies ◽

Biological Organization ◽

Trade Offs ◽

Wide Range ◽

Body Sizes

Organismal body size is an important biological trait that has broad impacts across scales of biological organization, from cells to ecosystems. Size is also deeply embedded in life history theory, as the size of an individual is one factor that governs the amount of available resources an individual is able to allocate to different structures and systems. A large body of work examining resource allocation across body sizes (allometry) has demonstrated patterns of allocation to different organismal systems and morphologies, and extrapolated rules governing biological structure and organization. However, the full scope of evolutionary and ecological ramifications of these patterns have yet to be realized. Here, we show that density-dependent larval competition in a natural population of insect parasitoids (Drino rhoeo: Tachinidae) results in a wide range of body sizes (largest flies are more than six times larger (by mass) than the smallest flies). We describe strong patterns of trade-offs between different body structures linked to dispersal and reproduction that point to life history strategies that differ between both males and females and individuals of different sizes. By better understanding the mechanisms that generate natural variation in body size and subsequent effects on the evolution of life history strategies, we gain better insight into the evolutionary and ecological impacts of insect parasitoids in tri-trophic systems.

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18. Comparing Relationships between Plant Body Sizes and Minimum Reproductive Threshold Sizes for Species of Contrasting Life History

Inquiry@Queen's Undergraduate Research Conference Proceedings ◽

10.24908/iqurcp.10122 ◽

2018 ◽

Author(s):

John Serafini

Keyword(s):

Life History ◽

Life Histories ◽

Natural Populations ◽

Early Death ◽

Life History Strategies ◽

Competitive Fitness ◽

Threshold Size ◽

Plant Life ◽

Body Sizes ◽

Disturbed Habitats

Two traits are fundamental in defining plant life history strategies: How big can a species get? And how big does it need to get before it can reproduce? Previous research has shown that there is a general positive relationship between these two traits, across species, and this can be accounted for as a trade-off. In this project, I explored whether this relationship differs among herbaceous species with perennial versus annual or biennial life histories. Perennials, because of their capacity to grow across several years, might generally be expected to display a relatively large MAX (maximum potential body size) and hence large MIN (minimum reproductive threshold size) compared with annuals or biennials that live only one or two years. In addition, annuals/biennials might be expected generally to have a smaller MIN for a given MAX, compared with perennials because of selection in the ancestral past — i.e. in frequently disturbed habitats, where annuals and biennials are common, predictable early death (from disturbance) has imposed strong selection to produce at least some offspring quickly, regardless of how small/suppressed the plant might be. I tested these predictions for resident plants sampled from natural populations of 105 species found in the vicinity of Kingston, Ontario. Remarkably, the results support neither prediction, and point to an alternative consequence of selection in shaping plant life history strategies; i.e. small MIN for a given MAX has also been favoured in perennials but for a different reason — as a strategy for competitive fitness.

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Determination of Adaptive Capacity for Flash Floods in Sri Lankan Context: Colombo City

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.c1004.0193s20 ◽

2020 ◽

Vol 9 (3S) ◽

pp. 19-24

Keyword(s):

Sri Lanka ◽

Adaptive Capacity ◽

Climate Changes ◽

Flash Flood ◽

Secondary Data ◽

Flash Floods ◽

Sri Lankan ◽

Management Actions ◽

Adaptive Index

Sri Lanka has witnessed many natural and anthropogenic disasters that have had a devastating impact on community and the economic welfare of the country. Disaster management actions are required to be taken to reduce disaster risk. Adaptive capacity is one of such measurements that can predict the resilience of the community. Climate changes directly effects on occurrences of disasters, especially on flash floods, which is one of the frequent disasters in Sri Lanka. The present research explained about developing an adaptive index for flash flood occurrences in the Colombo City, Sri Lanka. Secondary data were used to identify indicators of the index as well as to quantify the frequency and severity of the flash flood. Five determinants and 16 indicators were developed for the index by considering all 47 wards of Colombo city. All measurements were weighted by using a questionnaire survey and the results were normalized. Five determinants were mapped based on analyzed data and the highest vulnerability wards were identified. Mahawatte ward has the highest vulnerability followed by Wanathamulla and Bluemendhal. On the other hand, Kotehena East was observed as the lowest vulnerability ward followed by Wellawatte South and Wellawatte North.

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Potential of microcredit as a source of finance for development of Sri Lankan biogas industry

Energy & Environment ◽

10.1177/0958305x17714173 ◽

2017 ◽

Vol 28 (5-6) ◽

pp. 608-620 ◽

Cited By ~ 5

Author(s):

Tomáš Hes ◽

Samuel Mintah ◽

Haiyan Sulaiman ◽

Tuan Arifeen ◽

Petr Drbohlav ◽

...

Keyword(s):

Sri Lanka ◽

Annual Cost ◽

Service Providers ◽

Small Scale ◽

Sri Lankan ◽

Microfinance Institutions ◽

Economic Justification ◽

Biogas Plants ◽

Contractual Agreement ◽

National Technology

The study serves to clarify doubts on the potential of commercial microcredit as a strategic vehicle of implementing of small-scale biogas plants in Sri Lanka, as an alternative to subsidy-based process. The quantified sum of unsubsidized microloan interest born by the biogas users in a modeled situation of maximum potential of the biogas sector financed through microfinance institutions is compared with national technology savings on a macro level. The analysis concludes that an economic justification for the microfinance-fuelled implementation of small-scale biodigesters employing a market-based approach does exist. Annual savings on macroeconomic level surpass the annual cost expressed as a sum of unsubsidized interest. The study furthermore proposes a three-party credit contract, which prevents credit defaults caused by the lack of customary after-sales care by integrating the provision of service providers into a contractual agreement with both the user and the financing source, thus assuming part of credit responsibility.

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The Role of Music and Allied Arts in Public Writings on Cultural Diversity: “People of Sri Lanka”

ASIAN-EUROPEAN MUSIC RESEARCH JOURNAL ◽

10.30819/aemr.6-7 ◽

2020 ◽

Vol 6 ◽

pp. 93-100

Author(s):

Gisa Jähnichen

Keyword(s):

Sri Lanka ◽

Cultural Diversity ◽

South Asia ◽

Case Studies ◽

Sri Lankan ◽

Culturally Different ◽

The World ◽

Official Languages ◽

The Way

The Sri Lankan Ministry of National Coexistence, Dialogue, and Official Languages published the work “People of Sri Lanka” in 2017. In this comprehensive publication, 21 invited Sri Lankan scholars introduced 19 different people’s groups to public readers in English, mainly targeted at a growing number of foreign visitors in need of understanding the cultural diversity Sri Lanka has to offer. This paper will observe the presentation of these different groups of people, the role music and allied arts play in this context. Considering the non-scholarly design of the publication, a discussion of the role of music and allied arts has to be supplemented through additional analyses based on sources mentioned by the 21 participating scholars and their fragmented application of available knowledge. In result, this paper might help improve the way facts about groups of people, the way of grouping people, and the way of presenting these groupings are displayed to the world beyond South Asia. This fieldwork and literature guided investigation should also lead to suggestions for ethical principles in teaching and presenting of culturally different music practices within Sri Lanka, thus adding an example for other case studies.

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