Dubai Telegraph - Gray whales shrinking fast as climate warms

EUR -
AED 3.878381
AFN 70.7463
ALL 97.61914
AMD 408.610835
ANG 1.902881
AOA 962.990181
ARS 1056.133675
AUD 1.629831
AWG 1.903279
AZN 1.782367
BAM 1.961169
BBD 2.131736
BDT 126.165379
BGN 1.956257
BHD 0.39792
BIF 3059.500854
BMD 1.055911
BND 1.420876
BOB 7.295109
BRL 6.101267
BSD 1.05579
BTN 89.111243
BWP 14.492536
BYN 3.455159
BYR 20695.847018
BZD 2.128166
CAD 1.481395
CDF 3026.239678
CHF 0.937438
CLF 0.037319
CLP 1029.755569
CNY 7.634553
CNH 7.648657
COP 4732.327162
CRC 539.276272
CUC 1.055911
CUP 27.98163
CVE 110.765732
CZK 25.288741
DJF 187.656729
DKK 7.458477
DOP 63.830097
DZD 141.090833
EGP 52.228289
ERN 15.838658
ETB 128.873835
FJD 2.402218
FKP 0.833448
GBP 0.831266
GEL 2.877311
GGP 0.833448
GHS 16.947137
GIP 0.833448
GMD 74.96988
GNF 9113.563672
GTQ 8.153629
GYD 220.880478
HKD 8.217001
HNL 26.461494
HRK 7.532084
HTG 138.728456
HUF 406.280067
IDR 16819.863322
ILS 3.949333
IMP 0.833448
INR 89.184477
IQD 1383.770792
IRR 44459.114242
ISK 145.704916
JEP 0.833448
JMD 167.13754
JOD 0.74875
JPY 164.483941
KES 136.746848
KGS 91.20586
KHR 4277.493968
KMF 492.577276
KPW 950.319106
KRW 1481.96991
KWD 0.324608
KYD 0.879792
KZT 523.432901
LAK 23171.957081
LBP 94609.586688
LKR 308.454396
LRD 194.389971
LSL 19.270249
LTL 3.117829
LVL 0.63871
LYD 5.142547
MAD 10.51481
MDL 19.124993
MGA 4915.2638
MKD 61.493876
MMK 3429.556317
MNT 3587.984033
MOP 8.463609
MRU 42.104426
MUR 49.828585
MVR 16.313496
MWK 1833.060651
MXN 21.60902
MYR 4.731009
MZN 67.474328
NAD 19.270822
NGN 1773.781857
NIO 38.836002
NOK 11.721563
NPR 142.583725
NZD 1.797172
OMR 0.406548
PAB 1.05581
PEN 4.017209
PGK 4.154744
PHP 62.147202
PKR 293.595921
PLN 4.324907
PYG 8245.572309
QAR 3.844095
RON 4.976081
RSD 116.819612
RUB 104.856145
RWF 1441.317917
SAR 3.96598
SBD 8.852284
SCR 14.358481
SDG 635.128609
SEK 11.567089
SGD 1.418188
SHP 0.833448
SLE 23.948042
SLL 22141.921534
SOS 603.457557
SRD 37.333301
STD 21855.216762
SVC 9.23829
SYP 2653.006815
SZL 19.270107
THB 36.819919
TJS 11.254396
TMT 3.706246
TND 3.328196
TOP 2.473047
TRY 36.246349
TTD 7.168624
TWD 34.401037
TZS 2808.722543
UAH 43.524448
UGX 3874.606762
USD 1.055911
UYU 44.852785
UZS 13542.052761
VES 47.509864
VND 26820.128279
VUV 125.359824
WST 2.94767
XAF 657.745123
XAG 0.034607
XAU 0.00041
XCD 2.853651
XDR 0.79537
XOF 650.970195
XPF 119.331742
YER 263.819195
ZAR 19.211538
ZMK 9504.459219
ZMW 28.954812
ZWL 340.00277
  • RBGPF

    -0.9400

    59.25

    -1.59%

  • CMSC

    -0.0600

    24.55

    -0.24%

  • RYCEF

    -0.3200

    6.79

    -4.71%

  • BCC

    -2.2000

    140.35

    -1.57%

  • NGG

    0.2500

    62.37

    +0.4%

  • AZN

    -0.2500

    65.04

    -0.38%

  • GSK

    -0.7200

    34.39

    -2.09%

  • RELX

    -0.1700

    45.95

    -0.37%

  • VOD

    -0.0700

    8.68

    -0.81%

  • RIO

    -0.1900

    60.43

    -0.31%

  • SCS

    -0.1000

    13.27

    -0.75%

  • CMSD

    -0.0050

    24.725

    -0.02%

  • BCE

    -0.3700

    26.84

    -1.38%

  • JRI

    -0.0300

    13.21

    -0.23%

  • BTI

    0.0700

    35.49

    +0.2%

  • BP

    0.4800

    29.05

    +1.65%

Gray whales shrinking fast as climate warms
Gray whales shrinking fast as climate warms / Photo: ALFREDO ESTRELLA - AFP/File

Gray whales shrinking fast as climate warms

Pacific coast gray whales have shrunk in length an astonishing 13 percent since 2000, adding to evidence that climate change and other human activities are making marine mammals smaller, a study says.

Text size:

Their diminished size could have big impacts on survival rates and reproductive success -- and trigger ripple effects throughout their entire food webs.

For the paper, researchers focused on the Pacific Coast Feeding Group (PCFG) -- around 200 whales that are part of the wider Eastern North Pacific (ENP) population of around 14,500.

Considered "ecosystem sentinels," they stay closer to shore, feeding in shallower, warmer waters, than the wider population that inhabits colder, deeper Arctic seas. Prior research had shown they are in worse shape than their counterparts, with smaller bodies, heads and flukes.

"Now we know they have been shrinking in body size over the past 20-40 years, which may be an early warning sign that the population is at risk of declining," Kevin Bierlich, an assistant professor at Oregon State University and co-author of the paper in Global Change Biology, told AFP on Thursday.

By analyzing drone images taken from 2016-2022 of 130 individuals whose age was estimated or known, the scientists found a striking trend: a gray whale born in 2020 is likely to reach a full-grown adult length of approximately 1.65 meters (5ft 5in) less than a counterpart born in 2000.

This represents a significant 13 percent decrease in the total length of mature gray whales, which typically measure between 38-41 feet in length.

Notably, the decline was more pronounced in females, who historically exceeded males in size but are now comparable.

It would be the equivalent of seeing the average height of an American woman plummeting from 5ft 4in to 4ft 8in over two decades.

- Size matters -

"In general, size is critical for animals," said Enrico Pirotta, lead author on the study and a researcher at the University of St. Andrews in Scotland.

"It affects their behavior, their physiology, their life history, and it has cascading effects for the animals and for the community they're a part of."

Smaller whale calves may have lower survival rates when they stop weaning, while for adults, the major concern is reproductive success.

The species relies on energy reserves stored during the feeding season to support the demands of migration and reproduction during winter -- and the question arises whether they are able to put enough energy towards reproduction and keeping the population growing.

Importantly, the study found the trend was correlated with changes to the balance of "upwelling" and "relaxation" cycles of the ocean.

Upwelling transports nutrients from deeper waters to shallower areas. During relaxation periods, these nutrients remain in the shallower zones, where light enables plankton and other small species that whales feed on to grow.

Climate change is known to be an important factor affecting the dynamics of this delicate balance, through changes in wind patterns and water temperature.

A smaller stature may not only hinder whales' ability to thrive, but also increase their vulnerability to threats such as collisions with boats and entanglement in fishing gear, which can be deadly.

B.Gopalan--DT