Britain
1.
The impact of climate change (tỏc động của biến đổi khớ hậu /ði ˈɪmpổkt əv ˈklaɪmət ʧeɪndʒ/) on butterflies in Britain (đối với loài bướm ở Anh /ɒn ˈbʌtəflaɪz ɪn ˈbrɪtən/)
According to conservationists (nhà bảo tồn /ˌkɒnsəˈveɪʃənɪsts/), populations of around
two thirds of butterfly species (các loài bướm /ˈbʌtəflaɪ ˈspiːʃiz/) have declined (suy giảm
/dɪˈklaɪnd/) in Britain over the past 40 years. If this trend (xu hướng /trɛnd/) continues, it
might have unpredictable knock-on effects (những tác động không thể đoán trước được
/ˌʌnprɪˈdɪktəbl ˈnɒk ɒn ɪˈfɛkts/) for other species in the ecosystem (hệ sinh thái
/ˈiːkəʊˌsɪstəm/). Butterfly eggs (trứng bướm /ˈbʌtəflaɪ ɛgz/) develop into caterpillars (sâu
bướm /ˈkổtəˌpɪləz/) and these insects, which are the second stage in a new butterfly’s
lifecycle *(vòng đời /ˈlaɪfˌsaɪkəl/), consume vast quantities of plant material (vật liệu thực
vật /plɑːnt məˈtɪərɪəl/), and in turn act as prey (con mồi /preɪ/) for birds (chim /bɜːdz/) as
39 well as bats (dơi /bổts/) and other small mammals (động vật cú vỳ nhỏ /smɔːl ˈmổməlz/).
Only by arming themselves with an understanding of why butterfly numbers are down can conservationists hope to halt or reverse (ngăn chặn hoặc đảo ngược /hɔːlt ɔːr rɪˈvɜːs/) the
decline.
2.
Butterflies prefer outdoor conditions (điều kiện ngoài trời /ˈaʊtdɔːr kənˈdɪʃənz/) to be ‘just
right’, which means neither too hot nor too cold. Under the conditions of climate change, the temperature (nhiệt độ /ˈtɛmpərətʃər/) at any given time in summer is generally getting warmer, leaving butterflies with the challenge (thỏch thức /ˈʧổlɪndʒ/) of how to deal with
this. One of the main ways in which species are ensuring conditions suit them is by
changing the time of year (thay đổi thời gian trong năm /ˈʧeɪndʒɪŋ ðə taɪm əv jɪər/) at which
they are active and reproduce (sinh sản /ˌriːprəˈdjuːs/). Scientists refer to the timing of such lifecycle events (thời gian của các sự kiện vòng đời như vậy /ˈtaɪmɪŋ əv sʌʧ ˈlaɪfˌsaɪkəl ɪˈvɛnts/) as ‘phenology’ (hiện tượng học /fɪˈnɒləʤi/), so when an animal or
plant starts to do something earlier in the year than it usually does, it is said to be ‘advancing its phenology’.
3.
These advances (tiến bộ /ədˈvɑːnsɪz/) have been observed already in a wide range of
butterflies – indeed, most species are advancing their phenology to some extent. In Britain, as the average spring temperature (nhiệt độ trung bỡnh mựa xuõn /ˈổvərɪʤ sprɪŋ ˈtɛmpərətʃər/) has increased by roughly 0.5°C over the past 20 years, species have
advanced by between three days and a week on average, to keep in line with cooler temperatures. Is this a sign that butterflies are well equipped to cope with (đối phó với /koʊp wɪð/) climate change, and readily adjust (dễ dàng điều chỉnh /ˈrɛdɪli əˈʤʌst/) to new
temperatures? Or are these populations under stress (căng thẳng /strɛs/), being dragged
along unwillingly by unnaturally fast changes? The answer is still unknown, but a new study is seeking to answer these questions.
4.
First, the researchers (các nhà nghiên cứu /rɪˈsɜːrtʃərz/) pulled together data from millions of records (hồ sơ, ghi chép /ˈrekərdz/) that had been submitted by butterfly enthusiasts
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(những người yờu thớch bướm /ˈbʌtəflaɪ ɪnˈθuːziổsts/) – people who spend their free time
observing (quan sát /əbˈzɜːrvɪŋ/) the activities of different species. This provided
information on 130 species of butterflies (loài bướm /ˈspiːʃiz əv ˈbʌtəflaɪz/) in Great Britain
every year for a 20-year period. They then estimated the abundance (sự phong phú /əˈbʌndəns/) and distribution (sự phân bố /ˌdɪstrɪˈbjuːʃən/) of each species across this
time, along with how far north (phía bắc /nɔːrθ/) in the country they had moved. The data
also, crucially (quan trọng /ˈkruːʃəli/), allowed researchers to estimate subtle changes
(những thay đổi nhỏ /ˈsʌtl ʧeɪndʒɪz/) in what time of the year each species was changing
into an adult butterfly (bướm trưởng thành /əˈdʌlt ˈbʌtəflaɪ/).
5.
Analyzing the trends (phõn tớch cỏc xu hướng /ˈổnəlaɪzɪŋ ðə trɛndz/) in each variable
(biến số /ˈvɛəriəbl/), the researchers discovered that species with more flexible lifecycles
(vòng đời linh hoạt /ˈflɛksɪbl ˈlaɪfsaɪklz/) were more likely to be able to benefit from an
earlier emergence (sự xuất hiện /ɪˈmɜːrdʒəns/) driven by climate change. Some species
are able to go from caterpillar to butterfly (từ sõu bướm đến bướm /ˈkổtəˌpɪlər tə ˈbʌtəflaɪ/) twice or more per year, so that the individual butterflies you see flying in the
spring are the grandchildren (chỏu /ˈɡrổntʃɪldrən/) or great-grandchildren (chắt /ˌɡreɪtˈɡrổntʃɪldrən/) of the individuals seen a year previously.
6.
Among these species, researchers observed that those which have been advancing their phenology (đẩy nhanh thời kỳ sinh trưởng /ədˈvổnsɪŋ ðeə fɪˈnɒləʤi/) the most over the
20-year study period also had the most positive trends in abundance (sự phong phú /əˈbʌndəns/), distribution (sự phân bố /ˌdɪstrɪˈbjuːʃən/) and northwards extent (phạm vi
phía bắc /ˈnɔːrθwərdz ɪkˈstɛnt/). For these species, such as Britain’s tiniest butterfly, the dainty mall Blue, whose colonies (các đàn /ˈkɒləniz/) are up to a hundred strong, some develop into butterflies early in spring, allowing their summer generations (thế hệ mùa hè
/ˈsʌmər ˌdʒɛnəˈreɪʃənz/) to complete another reproductive cycle (chu kỳ sinh sản /ˌriːprəˈdʌktɪv ˈsaɪkl/) by autumn so that more population growth (tăng trưởng dân số /ˌpɒpjʊˈleɪʃən ɡroʊθ/) occurs.
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7.
Other species (các loài /ˈspiːʃiz/), however, are less flexible (linh hoạt /ˈflɛksɪbl/) and
restricted to a single reproductive cycle (chu kỳ sinh sản /ˌriːprəˈdʌktɪv ˈsaɪkl/) per year.
For these species, there was no evidence of any benefit (lợi ích /ˈbɛnɪfɪt/) to emerging earlier (xuất hiện sớm hơn /ɪˈmɜːdʒɪŋ ˈɜːrlɪər/). Indeed, worryingly, it was found that the
species in this group that specialize (chuyên về /ˈspɛʃəlaɪz/) in very specific habitat types
(loại mụi trường sống /ˈhổbɪtổt taɪps/), often related to the caterpillar’s preferred diet
(chế độ ăn ưa thích của sâu bướm /prɪˈfɜːrd ˈdaɪət/), actually tended to be most at harm
from advancing phenology (bị tổn hại nhất từ việc đẩy nhanh thời kỳ sinh trưởng /hɑːrm frəm ədˈvổnsɪŋ fɪˈnɒləʤi/). The beautiful High Brown Fritillary, often described as
Britain’s most endangered butterfly (loài bướm nguy cấp nhất ở Anh /ɪnˈdeɪndʒərd
ˈbʌtəflaɪ/), is in this group. It is found only in coppiced woodland (rừng đã cắt tỉa /ˈkɒpɪst
ˈwʊdlənd/) and limestone pavement habitats (môi trường sống trên đá vôi /ˈlaɪmstoʊn ˈpeɪvmənt ˈhổbɪtổts/). It is also a single-generation butterfly that has advanced its phenology. This suggests that climate change, while undoubtedly not the sole cause, might have played a part in the downfall (sự suy giảm /ˈdaʊnfɔːl/) of this species.
8.
All is not lost, however. Many of Britain’s single-generation species show the capacity (khả năng /kəˈpổsɪti/), in continental urope (chõu Âu lục địa /ˌkɒntɪˈnɛntl ˈjʊərəp/), to add a second generation in years that are sufficiently warm (đủ ấm /səˈfɪʃəntli wɔːrm/).
Therefore, as the climate continues to warm (ấm lên /wɔːrm/), species like the ilver- studded Blue might be able to switch to multiple generations (nhiều thế hệ /ˈmʌltɪpl ˌdʒɛnəˈreɪʃənz/) in the UK as well, and so begin to extract benefits from the additional warmth (sự ấm áp thêm /əˈdɪʃənl wɔːrmθ/), potentially leading to population increases
(gia tăng dân số /ˌpɒpjʊˈleɪʃən ˈɪnˌkriːsɪz/).
9.
More immediately, conservationists (nhà bảo tồn /ˌkɒnsəˈveɪʃənɪsts/) can arm
themselves with all this knowledge to spot the warning signs (phát hiện dấu hiệu cảnh báo
/spɒt ðə ˈwɔːrnɪŋ saɪnz/) of species that may be at risk (nguy cơ /rɪsk/). The White Admiral
of southern ngland (miền Nam nước Anh /ˈsʌðərn ˈɪŋɡlənd/), a much sought-after
42 butterfly, experienced a significant increase (sự gia tăng đáng kể /sɪgˈnɪfɪkənt ˈɪnˌkriːs/) in numbers from the 1920s but has shown a considerable decline (sự suy giảm đáng kể /kənˈsɪdərəbl dɪˈklaɪn/) in the past 20 years. This may be because the caterpillar exists
solely on a diet of a plant called honeysuckle (cây kim ngân /ˈhʌnɪˌsʌkl/). But it is also likely to be due to climate change (biến đổi khí hậu /ˈklaɪmət ʧeɪndʒ/).