Climate-driven range shift prompts species replacement

Climate change is regarded as one of the most important threats to plants. Already species around the globe are showing considerable latitudinal and altitudinal shifts. Helen’s bee orchid (Ophrys helenae), a Balkan endemic with a distribution center in northwestern Greece, is reported to be expanding east and southwards. Since this southeastern movement goes against the usual expectations, we investigated via Species Distribution Modelling, whether this pattern is consistent with projections based on the species’ response to climate change. We predicted the species’ future distribution based on three different climate models in two climate scenarios. We also explored the species’ potential distribution during the Last Interglacial and the Last Glacial Maximum. O. helenae is projected to shift mainly southeast and experience considerable area changes. The species is expected to become extinct in the core of its current distribution, but to establish a strong presence in the mid- and high-altitude areas of the Central Peloponnese, a region that could have provided shelter in previous climatic extremes.

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North Atlantic warming over six decades drives decreases in krill abundance with no associated range shift

Communications Biology ◽

10.1038/s42003-021-02159-1 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Martin Edwards ◽

Pierre Hélaouët ◽

Eric Goberville ◽

Alistair Lindley ◽

Geraint A. Tarling ◽

...

Keyword(s):

North Atlantic ◽

Range Shift ◽

The Core ◽

Krill Abundance ◽

The North ◽

Living Space ◽

Warming Climate ◽

Two Temperatures ◽

The North Atlantic

AbstractIn the North Atlantic, euphausiids (krill) form a major link between primary production and predators including commercially exploited fish. This basin is warming very rapidly, with species expected to shift northwards following their thermal tolerances. Here we show, however, that there has been a 50% decline in surface krill abundance over the last 60 years that occurred in situ, with no associated range shift. While we relate these changes to the warming climate, our study is the first to document an in situ squeeze on living space within this system. The warmer isotherms are shifting measurably northwards but cooler isotherms have remained relatively static, stalled by the subpolar fronts in the NW Atlantic. Consequently the two temperatures defining the core of krill distribution (7–13 °C) were 8° of latitude apart 60 years ago but are presently only 4° apart. Over the 60 year period the core latitudinal distribution of euphausiids has remained relatively stable so a ‘habitat squeeze’, with loss of 4° of latitude in living space, could explain the decline in krill. This highlights that, as the temperature warms, not all species can track isotherms and shift northward at the same rate with both losers and winners emerging under the ‘Atlantification’ of the sub-Arctic.

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A Doppler Range Compensation for Step-Frequency Continuous-Wave Radar for Detecting Small UAV

Sensors ◽

10.3390/s19061331 ◽

2019 ◽

Vol 19 (6) ◽

pp. 1331

Author(s):

Massimiliano Pieraccini ◽

Lapo Miccinesi ◽

Neda Rojhani

Keyword(s):

Short Range ◽

Continuous Wave ◽

Range Shift ◽

Specific Method ◽

Step Frequency ◽

Wave Radar ◽

Small Uav ◽

The Doppler Effect ◽

Set Up ◽

Free Falling

Step-frequency continuous-wave (SFCW) modulation can have a role in the detection of small unmanned aerial vehicles (UAV) at short range (less than 1–2 km). In this paper, the theory of SFCW range detection is reviewed, and a specific method for correcting the possible range shift due to the Doppler effect is devised. The proposed method was tested in a controlled experimental set-up, where a free-falling target (i.e., a corner reflector) was correctly detected by an SFCW radar. This method was finally applied in field for short-range detection of a small UAV.

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Predicting range-shift success potential for tropical marine fishes using external morphology

Biology Letters ◽

10.1098/rsbl.2016.0505 ◽

2016 ◽

Vol 12 (9) ◽

pp. 20160505 ◽

Cited By ~ 9

Author(s):

Shannen M. Smith ◽

Rebecca J. Fox ◽

Jennifer M. Donelson ◽

Megan L. Head ◽

David J. Booth

Keyword(s):

Fish Larvae ◽

Climatic Conditions ◽

Invasion Success ◽

Range Shift ◽

Tropical Fish ◽

Range Shifts ◽

Native Community ◽

The Family ◽

Moorish Idol ◽

New Habitats

With global change accelerating the rate of species' range shifts, predicting which are most likely to establish viable populations in their new habitats is key to understanding how biological systems will respond. Annually, in Australia, tropical fish larvae from the Great Barrier Reef (GBR) are transported south via the East Australian Current (EAC), settling into temperate coastal habitats for the summer period, before experiencing near-100% mortality in winter. However, within 10 years, predicted winter ocean temperatures for the southeast coast of Australia will remain high enough for more of these so-called ‘tropical vagrants’ to survive over winter. We used a method of morphological niche analysis, previously shown to be an effective predictor of invasion success by fishes, to project which vagrants have the greatest likelihood of undergoing successful range shifts under these new climatic conditions. We find that species from the family of butterflyfishes (Chaetodontidae), and the moorish idol, Zanclus cornutus , are most likely to be able to exploit new niches within the ecosystem once physiological barriers to overwintering by tropical vagrant species are removed. Overall, the position of vagrants within the morphospace was strongly skewed, suggesting that impending competitive pressures may impact disproportionately on particular parts of the native community.

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