European Journal of Ecology

Germination rates of old and fresh seeds and their implications on invasiveness of the ornamental Canary Islands date palm (Phoenix canariensis)

Dirk HR Spennemann, Melissa Pike, Wayne Robinson — Thu, 31 Dec 2020 00:00:00 -0600

In many countries, Canary Islands Date Palms (Phoenix canariensis) have escaped their horticulturally managed settings and have commenced to colonise surrounding natural bushland. While dispersed by various vectors, both birds and canids such as foxes, fluctuating environmental conditions may inhibit germination in the season of deposition. The potential of old, previous season’s seeds to germinate when conditions turn favourable has direct implications on the plant’s ability to establish viable, colonising populations. Nothing is known about the ability of older, previous season’s seeds to successfully germinate.

Based in experimental data, this paper shows that that the seeds of Phoenix canariensis exhibit both substantial inter-specimen and inter-seasonal variations in their germination potential. The observed variability is caused by the high genetic diversity inherent in a given palm population, as well as by range of environmental factors. At the present stage it is impossible to separate these two. Directions for further research are outlined.

An ethnobotanical survey of spontaneous plants used in traditional medicine in the region of Aures, Algeria

Karim Baziz, Rim Tinhinene Maougal , Abdelkader Amroune — Thu, 31 Dec 2020 00:00:00 -0600

This study carried out in the Aures region (Algeria) between September 2018 and March 2019, allowed us to identify spontaneous plants used in the region and gather all the information concerning the therapeutic practices of the local population. Based on a series of ethnobotanical surveys, we have identified 112 medicinal species belonging to 49 families, of which Asteraceae, Poaceae, Lamiaceae, Fabaceae, Amaranthaceae and Cupressaceae are the most represented. The leaves were the most used plant parts (28.86%), and the decoction (37.68%) represents the most frequently used mode of preparation. In addition, the remedies were prepared essentially from single species (81.15%) and were used mainly in the treatment of digestive disorders (23.99%). The study has also shown that women, married people, the elderly and illiterates people had the better knowledge of the use of medicinal plants.

These results indicate that local population has a fairly deep empirical and traditional knowledge of phytotherapy. However, this knowledge is endangered mainly because of the mode of transmission which is based on oral tradition and an urgent transcription is needed to avoid the loss of this heritage.

Birds crossing over roads: species, flight heights and infrastructure use

Betleja Jacek, Łukasz Jankowiak, Tim H. Sparks , Piotr Tryjanowski — Thu, 31 Dec 2020 00:00:00 -0600

How high do birds fly above roads, and how do they use the road infrastructure (bridges, lampposts etc.)? These questions are rarely explored in ecological studies but were addressed by us during research in 2016–2018 in southern Poland. In total, 1665 individual birds belonging to 24 species were recorded. Species differed significantly in the height at which they crossed over roads, but about 30% of all crossings were at heights below 12 m, hence at potential collision heights. The proportion of birds perching on lampposts in the central reservation between carriageways also differed significantly between species. The surrounding landscape and road infrastructure, especially lampposts, modified the species composition associated with roads. This knowledge has practical importance, not only in regard to collisions, but also to much less studied aspects such as plant seed dispersal and/or corrosion of the infrastructure. Lampposts, as a taller component of the infrastructure, may not directly affect vehicle-bird collisions, but a flight to them may be a risky business, and we recommended higher lampposts to discourage low-level flights. This information may need to be incorporated into future studies on road ecology, as well as in mitigation programs.

Maximum Entropy Niche Modelling to Estimate the Potential Distribution of Phytophthora megakarya (Brasier & M. J. Griffin) in Tropical Regions

Maxwell Obiakara, Peter M. Etaware, Kanayo S. Chukwuka — Thu, 31 Dec 2020 00:00:00 -0600

Background: Phytophthora megakarya is an invasive pathogen endemic to Central and West Africa. This species causes the most devastating form of black pod disease. Despite the deleterious impacts of this disease on cocoa production, there is no information on the geographic distribution of P. megakarya.

Aim: In this study, we investigated the potential geographic distribution of P. megakarya in cocoa-producing regions of the world using ecological niche modelling.

Methods: Occurrence records of P. megakarya in Central and West Africa were compiled from published studies. We selected relevant climatic and edaphic predictor variables in the indigenous range of this species to generate 14 datasets of climate-only, soil-only, and a combination of both data types. For each dataset, we calibrated 100 candidate MaxEnt models using 20 regularisation multiplier values and five feature classes. The best model was selected from statistically significant candidates with an omission rate ≤ 5% and the lowest Akaike Information Criterion corrected for small sample sizes, and projected onto cocoa-producing regions in Southeast Asia, Central and South America. The risk of extrapolation in model transfer was measured using the mobility-oriented parity (MOP) metric.

Results: We found an optimal goodness-of-fit and complexity for candidate models incorporating both climate and soil data. Predictions of the model with the best performance showed that nearly all of Central Africa, especially areas in Gabon, Equatorial Guinea, and southern Cameroon are at risk of black pod disease. In West Africa, suitable environments were observed along the Atlantic coast, from southern Nigeria to Gambia. Our analysis suggested that P. megakarya is capable of subsisting outside its native range, at least in terms of climatic and edaphic factors. Model projections identified likely suitable areas, especially in Brazil and Colombia, from southwestern Mexico down to Panama, and across the Caribbean islands in the Americas, and in Sri Lanka, Indonesia, Malaysia, and Papua New Guinea in Asia and adjacent areas

Conclusion: The outcomes of this study would be useful for developing measures aimed at preventing the spread of this pathogen in the tropics.

Induced alloparental care in Common Swifts (Apus apus)

Amnon Hahn, Reuven Yosef — Wed, 18 Nov 2020 00:00:00 -0600

The Common Swift, in spite of being considered to be of Least Concern, is declining in many areas of its breeding range. In several countries nest-box programs have been initiated to counter these declines. In most cases, when nestlings fall out of their nests, they are taken to rehabilitation centres. Raising and caring for Common Swift nestlings is not easy, cheap and usually results in low survival rates. We experimented with introducing the rescued young into existing nests and found that they were readily accepted and all five of the young fledged successfully. We recommend alloparenting as the preferred option when precocial nestlings are rescued and active nests of other pairs are available.

Herpetofaunal diversity and community structure in the Murchison Falls - Albert Delta Ramsar site, Uganda

Mon, 07 Sep 2020 00:00:00 -0500

1. The area of the Murchison Falls-Albert Delta is among the most important for conservation in East Africa due
to the high species richness, and the presence of several endemic species of conservation concern.
2. Here, we report a study on the diversity patterns and community structure of the herpetofauna of this area.
3. Field studies were conducted in the Albert Nile Delta Ramsar site between 1st October 2017 and 9th September
2018. The data collection relied on Visual Encounter Surveys (VES), pitfall trapping, and dip netting. Descriptive statistics, i.e. species numbers in each transect were used as a measure of the present biodiversity, whereas
Chao1 and Chao species estimator algorithms were used to predict the potential number of species found in
each site/habitat.
4. A total of 898 individuals representing 25 reptile species belonging to four orders, 15 families, and 20 genera
were recorded during the 12 months of surveys.
5. The data shows some non-random spatial and temporal patterns whereby there is a cyclic reptilian diversity
peaking during the December-March and again towards June-August-September which are peaks of the dry
season.
6. The most frequently encountered species were Varanus niloticus, Crocodylus niloticus, Agama agama, Trachylepis maculilabris, and Lygodactylus guttularis, which accounted for almost 90% of all recorded individuals.
7. A total of 27 amphibian species, belonging to nine families and 10 genera were recorded during the period
of the survey. The diversity and abundance graphs would indicate amphibians having bimodal peaks (September-December, and March-May). The diversity seemed to dip during the dry season months – which is the
opposite case for reptiles.