Metadata-Version: 2.5
Name: polar-biodiversity-utac
Version: 1.0.0
Summary: Real polar biodiversity trends across both poles, broad-spectrum with a focus on penguins, polar bears, and whales (population/breeding data, krill/food-web base, seals/seabirds/walrus, terrestrial biodiversity), no UTAC/CREP/AFET bridge
Project-URL: Homepage, https://github.com/GenesisAeon/polar-biodiversity-utac
Project-URL: Repository, https://github.com/GenesisAeon/polar-biodiversity-utac
Author: Römer, Johann
License: MIT
License-File: LICENSE
Requires-Python: >=3.11
Provides-Extra: dev
Requires-Dist: mypy>=1.10.0; extra == 'dev'
Requires-Dist: pre-commit>=3.7.0; extra == 'dev'
Requires-Dist: pytest-cov>=5.0.0; extra == 'dev'
Requires-Dist: pytest>=8.0.0; extra == 'dev'
Requires-Dist: ruff>=0.6.0; extra == 'dev'
Description-Content-Type: text/markdown

# polar-biodiversity-utac

GenesisAeon Package 128 — real polar biodiversity trends across both
poles, broad-spectrum with a deliberate focus on penguins, polar bears,
and whales. Third sibling to `antarctic-ice-shelf-utac` (P120) and
`arctic-climate-utac` (P127). **Deliberately has no UTAC/CREP/AFET
bridge** — see [DISCLAIMER.md](DISCLAIMER.md).

For a plain-language explanation of the same topic (German, no jargon,
written for general audiences), see [WHITEPAPER.md](WHITEPAPER.md).

## Where this package came from

Johann asked specifically about penguin population/breeding-site
trends, flagged as alarming, and explicitly requested this not be
limited to penguins/polar bears/whales — a genuine broad-spectrum
survey, with those three as the focus rather than the whole scope.
Built via six parallel independent research passes, each required to
find real citable primary/near-primary sources.

## What's real here

- **Penguins** — Emperor: 4 of 5 monitored Bellingshausen Sea colonies
  suffered total breeding failure in 2022 when sea ice broke up early
  (Fretwell et al. 2023). Chinstrap: globally ~3.42M breeding pairs;
  40.4% of colonies declined but 16.2% increased, and 57.6% of the
  total population isn't significantly changing (Strycker et al.
  2020). Adélie: nearly doubled in East Antarctica since the 1980s,
  declining at the Western Antarctic Peninsula — sharply regional, not
  uniform. Gentoo: the outlier, actively expanding southward.
- **Polar bears** — of 19 IUCN/PBSG subpopulations: 2 likely
  increasing, 5 likely stable, 3 likely decreasing, 9 data-insufficient.
  Western Hudson Bay: ~50% decline over 4 decades, mechanistically
  linked to shortened hunting seasons (Archer et al. 2025). Davis
  Strait: a real abundance change with no statistically significant
  climate/ice/prey effect detected (Dunham et al. 2024).
- **Whales** — Southern Hemisphere humpback: recovered to ~93% of
  pre-exploitation abundance (Zerbini et al. 2019). Antarctic blue
  whale: still at roughly 0.7–1% of pre-whaling levels. Savoca et al.
  (2024): krill catch up 4x since 1993 — recovery and fishery expansion
  are in genuine tension, krill biomass can't support both.
- **Food-web base** — Antarctic krill distribution has contracted
  southward over 90 years (Atkinson et al. 2019); sea ice is critical
  larval-overwintering habitat (Sylvester et al. 2025). Arctic
  phytoplankton productivity rose 57% (1998–2018) under sea-ice loss —
  more open water is not straightforwardly bad for productivity itself.
- **Seals/seabirds/walrus** — Signy Island: Weddell seals down 54%,
  Antarctic fur seals down 47% (1977–2024, Dunn et al. 2025). Pacific
  walrus mass haul-outs are real, but USGS states neither current
  abundance estimate establishes a population trend. Southern Ocean
  albatross decline is primarily fisheries-bycatch-driven, not climate.
- **Terrestrial** — Antarctic Peninsula vegetated area grew from 0.863
  to 11.947 km² (1986–2021, Roland et al. 2024) — real, but
  methodologically contested. Caribou/reindeer: 31 documented declines
  of 25–99% across 12 populations, driven by rain-on-snow icing events
  blocking forage access (Tyler 2010).

## Deliberately not one-note

Every module contains at least one real finding that complicates a
uniform "everything is collapsing" story — see DISCLAIMER.md for the
full list. This does not mean the picture is fine; several modules
document genuinely severe declines. It means every number here is
reported at the resolution the literature actually supports.

## Installation

```bash
pip install polar-biodiversity-utac
```

## Quick start

```python
from polar_biodiversity_utac import (
    CHINSTRAP, HUMPBACK, STATUS_BREAKDOWN,
    is_chinstrap_decline_global_or_regional,
    is_every_pygoscelis_penguin_declining,
)

is_chinstrap_decline_global_or_regional()  # "regional"
is_every_pygoscelis_penguin_declining()    # False -- Gentoo expands
STATUS_BREAKDOWN.increasing                # 2 of 19 polar bear subpopulations
HUMPBACK.pct_of_pre_exploitation           # 93.0
```

## License

Code: MIT. Documentation/data notes: see [DISCLAIMER.md](DISCLAIMER.md).

## Citation

See [CITATION.cff](CITATION.cff).
